Try it, steam makes it so easy to refund stuff assuming you played less than couple hours and bought it fairly recently. And forcing companies to make trials isn't as easy as you think. Some indie games still have trial versions but those are pretty much impossible to find in AAA titles as they obviously want people to just buy them and play past the return window.
Edit: Also on your post, who cares? Lot of companies certainly don't have morals and do whatever they can to milk their users. If you don't wanna pay for it then don't, its better than not playing anyway. Buy something if you can afford to and wanna support the studio, especially indie studios who rely on that income to produce more games and the money actually go to the people who deserve it. I personally just grab a bunch of stuff on sale and play one when I feel like it, although a lot of them remains untouched to this date.
Tldr: don't overthink it, do whatever works for you