Not really a bug per say but I do feel like feeders should make more/contribute more once PC becomes immobile. Also I'm sure you're already working on it but having a feedee upgrade system seems appropriate now too. Something to help lose and gain weight faster, gain and lose fitness faster and make feedees want to feed you more would be cool.
It would make the game feel more robust but it's only if it's in your interest. At the current moment, if you interact with a feeder there's no way to really level up your OWN feeder perks aside from self control obviously, but I'm also of the impression that if you continue to deny them dates they'll lose interest. For me at least, this means that I kinda wanna hold off on even MEETING feeders until I finish my OWN feeder perks and then indulge in gluttony after I've made enough passive income from Dizzy's.
Oh and speaking of I do think there's some bugs for being a feedee and getting meals from feeders. I'm assuming the feeders are supposed to pay always but certain events like the town food festival and the bake sale still deduct money from your total.
That does make sense, it'd help make being a feedee feel less tacked on if you could earn XP and upgrades from gaining weight yourself. I'd like players to be able to play how they want without feeling like they're missing out by doing so.
Alternative ways of making money could help, so you don't need to rely on the doughnut shop or feeder upgrades that boost money earned.
You're right that it didn't make sense to still have to pay for those events when with a feeder. One of the bug-fix updates I released this weekend addressed that, so hopefully those are showing up as free for you now (when you're there with a feeder).