Brick Joke: The seat David was about to get was him between two fat passengers before he sat with Buddy. The end of the movie reveals that the air marshal ended up taking that seat, adding to his bad day.
For the Evulz: Subverted. In between we're given the impression of Buddy as a rather nutty Cloudcuckoolander (which he is by the way) who appears to be torturing Dave just for the fun of his twisted little games, though in end, it turns out that Buddy's Zany Scheme really was just to help Dave overcome his implosive anger problems to get him to stand up for himself.
Girl on Girl Is Hot: Subverted, as Dave is more creeped out by the gorgeous bisexuals who are his fellow therapy group members than aroused by them.
Have a Gay Old Time: Buddy forces Dave to pull his car over on the side of the highway and sing the song "I Feel Pretty." Dave's intonation of "I feel pretty and witty and gay" indicates that he recognizes this trope, and he's feeling both emasculated and humiliated.
I'm Not Angry: David's shtick for most of the film and he hides the anger pretty well, up until he finally snaps at his Jerkass boss and co-worker.
Jack Nicholson: The Guardian`s review of the film described it as starring "Jack Nicholson playing a Jack Nicholson who's not as good a Jack Nicholson as the Jack Nicholson he played in About Schmidt or As Good As It Gets, but a better Jack Nicholson than the Jack Nicholson he played in Somethings Gotta Give.
Jerkass: Ironically, Sandler, who tends to play this character type, is here one of the few characters who does not fit that description.
What the Hell, Hero?: As part of his "therapy," Buddy takes Dave to a Buddhist retreat to confront the bully who used to torment him in school, who has now shaved his head and renounced all violence. Although the former bully now bears no ill will against Dave, Buddy proceeds to goad him into getting angry all over again, prompting a scene where Dave beats the guy up and "wedgies" him. Buddy then pulls a water gun on all the other monks, and he and Dave barely escape the compound with their lives.
To be fair, when Dave confronts the bully about pulling his pants down in front of his childhood crush, the bully is completely unapologetic about it, and in fact mocks him even further, proving that even though he's a Buddhist monk now, he's still very much a dick.
Wouldn't Hit a Girl: Played straight with the flight attendant, but later subverted when he hits the cocktail waitress, by accident.