Out of curiosity I bought a Chinese Helinox knockoff ($28 USD, shipped) which arrived the other day. It looks pretty good, though I've only used it for a few minutes, so far. Feels and looks the same as 'the real thing' (which I also own). https://www.aliexpress.com/item/32639825025.html?spm=a2g0s.9042311.0.0.f1c64c4doPUWLt Most of the time, I'm more of a 'sit on a log' kinda person. On a cold or wet day a sit pad is nice and it's also a handy kneeler at the tent entrance. Under $1.50 USD with shipping for 11" x 15" size, these are OK : https://www.aliexpress.com/item/32639825025.html?spm=a2g0s.9042311.0.0.f1c64c4doPUWLt It's hardly worth the trouble to find an old piece of closed cell foam and cut a chunk at that price, and they fold up accordion style.
I was a log person for years 'til I bought one those stadium seats. It was much more comfortable than the log. Then my partner bought a helinox-mec-knockoff. I poo-pooed it cuz, well cuz, until I sat in it when she wasn't looking and promptly fell asleep. I'm a convert.
I got a Joey Chair Model 7789 from Travel Chair. It isn't cheap but has a subtle refinement. There are flanges on the feet so they don't sink into soft ground or sand - at least not like a regular cylindrical chair leg. But like hammocks and cots, the chair can get a bit chill as cool winds rob the heat via convection loss. Just takes a little padding to stop that. Up to you to decide what "padding" will do.