1. It’s sexist towards both sexes. Let’s start with the ladies…
The classic Friend Zone assumption: if a woman complains to a man about her ex -- and eats half his fries, she owes him sex -- and the only reason she’s holding out is that she’s toying with him, or she doesn’t see the real him. “It makes the woman out to be irrational, close-minded, and harsh,” says Natasha Burton, author of The Little Black Book Of Red Flags. “In reality, maybe she just isn't interested. She's not putting a guy into some arbitrary box for no apparent reason.”
2. … but then there’s also the men
There's an ill-founded belief that if a guy does a woman a favor with no physical payoff, he’s a sucker. This presupposes that the man has no life outside his unrequited pining, a harsh judgment to pin on every single guy who ever drove a woman to the airport. We’re not saying that sex isn’t on men’s minds 24/7. But we are saying that outside of some outliers, most guys are perfectly capable of hanging out with women -- and even doing the occasional favor -- with no expectation of sex in return, and no emotional devastation when sex doesn’t happen.