Revealing mistake: When The Mask is dancing with Tina and he turns her into a human tornado while spinning her around, none of the onlookers in the crowd show the slightest bit of amazement at the impossible feat that just occurred in front of them, indicating that the extras were not directed to react to the special effects.
The Mask (1994)
Plot summary
Directed by: Chuck Russell
Starring: Cameron Diaz, Jim Carrey, Peter Riegert, Amy Yasbeck, Peter Greene
Stanley Ipkiss (Jim Carrey) is a bank clerk that is an incredibly nice man. Unfortunately, he is too nice for his own good and is a pushover when it comes to confrontations. After one of the worst days of his life, he finds a mask that depicts Loki, the Norse night god of mischief. Now, when he puts it on, he becomes his inner, self: a cartoony romantic wild man. However, a small time crime boss, Dorian Tyrel (Greene), comes across this character dubbed "The Mask" by the media. After Ipkiss's alter ego indirectly kills his friend in crime, Tyrel now wants this green-faced goon destroyed one way or the other.
Trivia: The set of the garage where Ipkiss has his car repaired is the same building as the Ghostbusters' headquarters (from the "Director Commentaries" in the DVD).
Question: Why would he have to steal the money from the bank? Given everything else he makes.
Answer: While under the influence of the mask, Stanley repeatedly gets revenge on people that have wronged him. The Mask wouldn't even need to create money out of thin air to get into the club since he could just use his powers to get in, so since he feels that he is mistreated at the bank, he robs it.
Answer: Nothing he makes while The Mask is permanent, and when separated from him reverts or disappears, as we see with the piece of pajama. If he made money, for example to get into the club, then immediately after giving it to the people and walking inside, it would vanish, probably causing him then to be thrown out. As Phaneron said, in addition, by robbing the bank to get it, he also strikes back at one of those he feels mistreats him.