If you don’t like the act that leads to reproduction, you’re less likely to reproduce meaning that your genes will probably not be represented on the next generation and therefore the likelihood of people not enjoying reproduction is generally low.
I guess that’s the whole point why most people tend to build some kind of relationship before jumping into bed. It’s not weird if there is trust and affection between the people involved. It’s also a basic instinct of most animals, it’s something you want so any awkwardness that may arise is secondary.
Simple: For most people (not everyone) even the thought of it releases stupid happy drugs in brain. It suppresses the feeling of disgust very effectively. Free will my ass, we are chained to those brain chemicals.
Weirdly enough a lot of humans are very opinionated on who are allowed to think about who, even if the brain chemicals doesn't give a shit. Its all a big mess really and earth would probably be better off if humans didn't produce these chemicals.