Is it "men should have to prove themselves for sex who shouldn't expect to get it easy from me" or "it's disgusting that men view sex as a prize to be won", which is it?

There was a deodorant ad that came on last night and my feminist sister made a remark expressing her disdain towards the idea of women being drawn into men. I told her that it's just a marketing ploy using the idea that men are biologically driven to want sex and see it as a reward for their efforts. Then she called me, "creepy" and went on some rant about "sex being commodified" and "women aren't machine where you do things for and sex falls out". I found those arguments to be very straw-man like and demonising towards men's sexual desire.

How is it any different to slut-shaming, or women seeking relationships, best organisms or how religious people demonise homosexuals. I told my sister that most women don't view sex as a reward because they're offered it constantly and can go out on a Friday night to get some whereas the average guy doesn't have that sort of abundant luxury, thus they view it as a reward.

Because women are very selective by nature and that males constantly have to prove themselves to be worthy, they'll either self-prove (gym) or bend over backwards (taking them out on multiple dates) in the hopes that she'll reward him with sex. Women don't like making themselves look "easy". Why is it so deplorable to seek out sex as a reward. It's only wrong if you lash out and say "fuck you bitch" if they turn you down but as long as there's honesty and that both parties move on, I don't see the harm.

My sister then also gives me a hypothetical scenario that imagine I buy drinks for a girl at a bar and then she goes off to snog some other guy, that it's me that apparently has a disgusting attitude for feelings disappointed. People are allowed to feel upset if they get turned down, it shouldn't make you a bad person and no one likes to be made into a chump (thus the alphafux/betabux thing). Even from personal experience, women use sex as a covert contract to try and gain something (relationships usually) then lash out if they don't get what they want.

Why do feminists have such a heavily, infringed attitude towards sex and male sexual desire?