I wonder how many men would react so badly at the end of a date, if the woman paid for her part; this way, the rejection might still hurt, but at least the man would not feel to be taken advantage of.

When the man pays for everything, instead (and this is what most women expect or even demand), he's kind of "investing" in a situation and hoping to get something in return.

Be real: everything we do, we do for a reason. "TANSTAAFL: There ain't no such thing as a free lunch." If one denies this, s/he's still believing in Santa Claus and unicorns.

Of course she doesn't "owe" him sex. But, OTOH, why it looks like she's "owed" a dinner instead? Can't you see this easily leads to confusion and bad feelings?