The wasting film is just part of the game, I have a big box full of wasted shots/shots that didn't come out how I wanted. Same thing with film photography too really. We're kind of spoiled now with digital photography because we can take as many shots as we want and delete the ones we don't like but that used to just be a given that some shots you take just won't come out as intended.
I shoot on both Polaroid and Instax film. They're both instant film but they're both really different with their own upsides and drawbacks. I find Instax film to be a lot more reliable and less "experimental" looking (not to mention cheaper), and just more stable in general -- Polaroid film can have some pretty insane color tints depending on the temperature when you shot the photo. Instax is also like 1/2-1/3rd of the price lol.
But then again, a lot of people genuinely like the look of Polaroid film. It appeals to people who want an imperfect photo on purpose. And a lot of the older Polaroid cameras are professional cameras that are just at a much higher level of quality and user control than anything available for Instax. So it just depends on what you want. It's a fun hobby, whenever I bring one of my cameras with me people always get excited and want to talk about. So it's a good icebreaker and good way to meet people in general.