Honestly, wouldn't it make more sense for the rate to go up *faster* as more towns get fatter? Since you're slowly gaining more and more of a following for Dizzy's with each established restaurant
I'd say that would make the game devolve into a hose feed-spam game, because you already use credits to upgrade your money output for your restaurant. It'd quickly ramp up both currencies and remove any challenge because you could just buy all the credits you need in every following town.
I haven't noticed anyone else mentioning this but a related thing is the tier 2 hose feed (the one you can buy for 1 credit each), has text that only shows up for 1 frame when you click away the quick-time buttons.