Comfy chairs aren't expensive and neither are croissants and sparkling water. There's no reason everyone couldn't have most of the lounge experience, but airports intentionally build uncomfortable seats and not enough of them. They want your experience to suck, because that's how they sell people on lounges. Same applies for basically anything that sucks about planes - it sucks because it's more profitable that way.

I went to a few lounges back when I got them for free and seeing how clear of a money grab and intentonal stratification they are made me not want to pay for them ever in the future.