Continuity mistake: The Green Goblin is impaled by the knives on his glider which are shown after they have punched through him and the brick wall, but there is no blood on them. (01:49:50)
Continuity mistake: At the beginning of the movie when the students are in a museum, we see a spider pulling up a sack of crickets. The sack changes position between shots. (00:07:00)
Continuity mistake: In the big carnival scene when the Green Goblin has thrown a bomb at the balcony the shot cuts to Peter and he sees two people about to get crushed by a falling rock. You can see that they are facing Peter with the woman on the right and the man on the left. The shot changes and they have their backs to Peter and the woman is now on the left, the man on the right. (01:04:15)
Continuity mistake: In the scene where Spider-Man wakes up after being gassed by Green Goblin, when Green Goblin puts his hand on Spider-Man, it's in a different position on his face in the following shot. (01:13:50)
Continuity mistake: At the start of the Unity Festival scene just after we see Peter taking a picture, it cuts to Macy Gray, in the first shot she is not holding onto the mic stand, yet in the following shot she is. (01:02:00)
Continuity mistake: When Peter has just seen MJ leave her house for school and is walking along the pavement by the cars following her, he stops when she does and practises talking to her. Look behind him. You can see the bus turning the corner and coming nearer to them. The shot stays on Peter when the bus rounds the corner, cuts to Mary Jane and then goes back to Peter. The bus would have been much nearer than it was in the second shot at the speed it's going. (00:20:00)
Continuity mistake: Near the end of the film the Green Goblin programs his glider to fly at Spider-Man, Spidey jumps out of the way and the glider continues to fly at the Green Goblin. You see a shot of the Green Goblin throwing his hands up next to his head, then a close-up shot of his face where he says "oh" but there are no hands. Then in the next shot from further away his hands are back by his head. (01:49:10)
Continuity mistake: In the scene where Spider-Man has saved MJ from the thugs, after they kiss she peels his mask back, note she is right next to his face, yet in the following shot she is much further away from his face. (01:18:20)
Continuity mistake: When Peter Parker goes up to his room, about to become Spider-Man, there's a sudden close-up of his face and his fringe looks different.
Continuity mistake: In the unity festival scene when the Green Goblin starts shooting at Spider-Man, he is about to run past the silver pushcart with an umbrella, yet when it cuts to a view from the Green Goblin, Spider-Man is quite some distance from that pushcart. (01:05:50)
Continuity mistake: In the middle of the film when we see Peter, Harry and Norman Osborn talking, Norman says "Perhaps you could tell me who she is, this mystery girl Harry's been dating" If you watch Harry, in one shot he has both arms on the table and in the following shot, he is one arm up and is scratching his head. (00:57:35)
Continuity mistake: When we see Norman Osborn testing out the formula with the other doctor, Norman comes back to life and grabs the other doctor, in the first shot from the front when he grabs him, his fingers and knuckles are straight against the doctors neck, yet from the back we see now its more of a fist. (00:16:50)
Continuity mistake: In the film Norman Osborn is talking to the board of the company where they announce they are selling the company. In one shot if you look on the table most of the folders that the board are holding are open. In the following shot most of them are closed. (01:00:30)
Continuity mistake: At the end of the film when we see MJ hugging Peter, in one shot you can see she moves her hand to his neck and close to his ear, yet from the front view, her hand is still on his back. (01:47:20)
Continuity mistake: When Spider-Man is fighting the thugs that attacked Mary Jane, at one point he lifts a thug in the air and they are in the middle of the street. After it cuts to Mary Jane, now Spider-Man is holding the thug in the air with one foot on the curb. (01:17:05)
Continuity mistake: In the fight with Flash Thompson (in school, his first fight), when Peter grabs his hand, first he is grabbing him by his watch, then a little bit lower in a different shot, in the next shot by his watch again. (00:23:40)
Continuity mistake: There's a purple tent below and to the right of where MJ is trapped on the breaking ledge. When the Goblin is kicked off of his glider by Spider-Man, he falls to MJ's left but lands in the tent on the right. (01:07:45)
Continuity mistake: While Peter is talking to Mr Jameson in his office around the middle of the film, he picks up the phone and calls in one of his assistants. When he suddenly appears at the door he moves the phone away from his ear twice. (01:11:25)
Continuity mistake: When the owners of Oscorp are asking Osborn questions, just after he says "back to formula," his position in the room changes within a second. (00:11:30)
Continuity mistake: At the Unity Festival, when the Green Goblin flies past on the glider, the camera cuts to a shot of the balcony, and behind Harry and MJ there is a man in a black suit that takes a picture (you can see the flash from the camera). But when the camera cuts to a close up, the camera that was in his right hand has vanished and is now a glass of wine. (01:03:40)
Answer: Remember that Green Goblin (Norman Osborne) just found out that Peter Parker is Spider-Man. Aunt May's comment about everyone knows he loves Mary-Jane concerns him because he now realizes that Green Goblin might find/kidnap Mary-Jane just to lure Spider-Man into a fight. This is the basis for the whole reason he can't be with her, as he would be potentially putting her in harm's way all the time if they got together.
Jazetopher