Hey I know this is a an oldish post but was just wondering if anyone found a solution to this? I've noticed the same bug!
Yea, this is one of those bugs that is annoying if you are player trying to be legitimate, especially with the Simple Living lot challenge. I get why its not on their priority list, but... yeah. They just need to remove "any mushroom" from the code for that canning recipe, and instead just add all the mushrooms, but I also get why that would be tedious.
EDIT: And yes, two years later, this bug is still in the game. Infinite mushroom conserves creation, just able to keep multiplying your jars.
