Jill's first tennis date is unavoidable. And your right it wouldn't make sense at all, that's why those scenes are forced.
Come on! Do you really want to turn this game into an open-world sandbox?
Or do you want even more choices than we already have, and wait 2 years for an update because the game has become so unmanageably complex? [You might want to try Element-174, where every single choice changes the game.]
Like most good developers, DrPinkCake has set parameters around which the game flows. They are his parameters and we are forced to accept them... or bitch about them... or quit.
He has given us girls to play with. They interact with the MC whether we like them or not. But he has also given us enough choices so that we can avoid almost all intimate contact with all of them. But they are still there, like the people at work or school that you don't get along with. These girls are needed for story progression.
Of course, all those choices mean that we have to do several playthroughs if we want to see all the content. I challenge anyone to play the game (as downloaded) on one route (without using a mod or the console to cheat), and unlock all the scenes in the gallery.