only here to tell you that since 2015, I’ve spent nearly around 15-20k on (on sale and non-on sale based on demand), in small projects demos (free). I haven’t made a fully featured commercial game yet, but mostly buy generic art assets, modular systems, etc. Think of something that it is used in most games and even AAA studios would want to save money on. Look at what PUBG did as well when they were starting. Instead of paying around 5k a month to an artist to do it from scratch, better pay 30 for an asset ( and the rest of that money can be spend in a new feature) IN ALL saves money, saves time, and great investment.
Edit:
Once in a while check on the request posts that developers make, if you believe it’s worth the time to develop, then go for it. The most you can waste is time and monthly membership that you were gonna be paying anyways(if at all).
I even have items no longer for sale in the marketplace either due to not support from sellers (abandoned) OR after non-copyright driven content movement last year.