In the Wolf of Wall Street, all of the founders are in Jordan's office and his dad, Max walks in and gets angry about how much theynhave spent on "dinner". Then Donnie says "It's okay, the IRA allows for T&A", then max corrects him saying its T&E and then Donnie argues with everyone that he did in fact say T&E, why does the movie show this?
2I think it's supposed to be a comedic moment, with Donnie giving a freudian slip (TNA = "Tits 'n' Ass) which, if he made the same slip in front of an IRA agent, could mean big problems.– TimMar 6, 2017 at 21:02
The four men are acting like children. They're trying to make each other laugh, because dad is so angry and they're supposed to be taking the situation seriously.
Donnie says "T&A" (which is slang for t*ts and a**) with the intention of making his friends laugh, knowing that he can cover it up by saying that he actually said T&E (which is a business term that means travel & expenses).
The scene was included overall to show that the men think they can do anything they want without getting in trouble. The "T&A" joke included just as another example of the men acting immature, and laughing when they should be taking something seriously.
He says T&A because they spent the money on strippers and hookers. I mean escorts, like the real life person whom the film is based on was known to do. He literally means he spent it on Tits and Ass. The father knows that EJ entertainment is some sort of escorts service. Its a flippant reply to Max, who as their accountant is already mad about the mess they are putting in his hands. And Donnie continues trying to bullshit his way through it. They argue because Max cares and Donnie doesn't.
It is shown that way to illustrate to the audience how ridiculous and irresponsible they are with money, squandering it away. They don't care cause they know they can get away with it and someone like Max will fix it. It's just another sequence building up the characters as the immature jackasses that they are. And because the movie is a slightly dramatized and exaggerated retelling of an autobiography, it's likely that a similar conversation happened.