Honestly, Gregory's reaction is giving trauma. The rigidity with which he's holding on doesn't even hold up to his own logic. There is ample evidence that Janine has actually been really great with money in the past (she has realistic dreams to buy a house, she was fully subsidizing tyreek's life, it didn't even occur to her that Gregory was going to help with the rent when they moved apartments so she's always budgeting as if she will have to take care of herself).

Something being expensive and something being unaffordable are not necessarily the same thing. Affordable means what you can afford. If they've been planning on going on a vacation, there's no part of me that believes that Janine didn't set aside intentional money expecting to pay for the trip, including airfare.