i have trouble doing any kind of sitting anyplace in any of our gardens. we have benches around but they mostly get used for setting things other than my butt. if i do happen to sit down it is rarely for longer than a few moments because i sit there and see all the things i need to do so then i get back up and start doing them. "What's that weed doing there in the pathway? Oh, yes, there's another weed a bit further off to the other side..."
the most common thing i am sitting on in many gardens is a ground pillow if i'm doing some weeding that takes closer vision or there's enough weeds in one location to make it worth sitting down to do. bending over is faster and easier if it's just a few weeds. pathway weeding of columbines, getting them out of the gravel is often an exercise in patience and a ground pillow for that is well worth it.