I've been asked to make covers for the cushions on an outdoor sofa.
I'm not hugely skilled at sewing but I think I could rustle up some covers, it just doesn't seem worth it to me. I think you could buy new cushions or at the very least new covers for not much more than the cost of fabric.
I think people who don't sew assume it must be cheaper. It was many years ago, when I was a child in the 60s my mother made all our clothes because she couldn't afford new.