Revealing mistake: When the kid in the store keeps knocking down the bottles and cans, you can see he barely grazes them, and yet they all fly off the shelves.
Continuity mistake: While sitting on the bench, near the lake, when Grandpa is telling John about out living everyone by eating bacon and smoking everyday, he has a cigarette in his left hand and a beer in his right hand. After a few minutes, when it switches back and forth from Grandpa to John, the cigarette and beer switch hands and then back again, between shots. (00:09:00)
Continuity mistake: When Jack & Walter drive to the fishing spot instead of the wedding, the exterior shots of the car show the Dodge Polara as a 4-door pillarless hardtop. When the interior of the car is shown, it is a four-door sedan, showing the thick pillar seen behind each man as they converse. As they speed back to the wedding, the four-door sedan now appears in a couple of exterior shots, and now the hardtop is used during interior shots of both men through the windshield.
Continuity mistake: When Max is eating his mac and cheese it changes camera shots rapidly. In one shot he's got some mac and cheese on his fork, in the next shot it's gone and the fork is clean. It does that a couple of times.
Visible crew/equipment: Half-way through the movie, in Max's and Maria's first kiss scene at night outdoors, 3 separate lighting goofs happen: A crew's spotlight is seen projecting from high in the trees on the left, then is quickly withdrawn. In a following shot, its beam reappears brightly spotlighting 'the worm.' Finally, when they're ready to embrace on the ground in very low light, the same pesky bright light jolts on, beaming right on them as they clinch. (00:55:00 - 01:05:00)