why is they slack until someone else makes a move

why is it guys get bitchy if another guy calls you beautiful, and act as if your cheating, yet when you are out and someone buys you a drink, or does something nice for you just because (simply to a genuine gentleman)

Only then to they feel the need to step up a bit.

uggh... yet you can tell them for MONTHS something you need or want(fav place for dinner, or what you want for Christmas) and they ingore it until someone else makes a move

so annoying.... uggh