On a recent date, they got thirsty so they stopped at a convenience store to get a bottle of water. They each grabbed their own and walked towards the cashier more or less together (she was walking slightly behind him). When he gets to the register, he pays only for HIS water when my friend is pretty much right behind him.
She said this has been bothering her a bit as she would have just paid for his water, too (because, I mean c'mon, it's only $2!)
If you were in her situation, would you also consider what he did to be really selfish? Isn't a relationship about a healthy balance of giving and taking?
Would you consider this a yellow flag (maybe not quite big enough to be red) that potentially shows that he won't be a generous, considerate boyfriend in the long run?