- Lots of indies DO have demos. That’s what Steam Next Fest is. Many of them are generous with playtime.
- Steam has a refund policy. In the event you find you made a mistake with a purchase, you can tell support it wasn’t fun.
- People are streaming a lot of games, even indies now. Those can give you a closer idea of even the midgame.
Lastly, I’m not going to use the S word that rhymes with Peel, because a dozen pirates will dogpile on how it’s not technically the correct terminology, but you’re still breaking a societal expectation - that people interested in another person’s work will pay for access to that work. Some museums will provide a donation box, but others have you pay for entry - Because artists gotta eat, and that’s the rule. No one cares you’re not lifting the paintings out of the hall. You have interest and curiosity, so pay some dues to the people who piqued that.