Yeah, seeing all the tiny off-cuts is what got me too. I read an article a while back that broke down how the foam doesn't really break down in landfills, it just crumbles into smaller and smaller bits. That stuck with me. Moss frames take a little more setup, but it feels way better to just dampen and reuse them.
Had the same exact thought about foam for years. What got me was seeing all the tiny off-cuts and trimmed pieces that just get tossed after one project. Switching to moss meant reusing the same base again and just adding fresh patches.