Wow, Thanks for the excellent write up!!
The first one I had known, I added a first pass check on the litter but it seems the order the functions were called would still allow +1 or so through testing. I figured for a game jam it would be alright but in a real game I would definitely verify all checks before adding.
As for the second point, I did not even consider limiting sound effects. I will need to look into that for Unity! For my own personal game I added separate sound channels and had the works for controls, but for this I thought that one channel would have been fine. Good to know it can break like that!!
I also LOVE the garbage depot being the shop! If I was doing any kind of updates I would for sure add that!
Thank you again for all the awesome feedback!!!