I always viewed those parts as demonstrating why The Culture / SC needs to get involved and fuck stuff up. That is, why the Prime Directive and non-interference are bunk, why we should get involved. The world/universe is a shitty place, so we need to make it better. And most of the protagonists have a stop on a GSV for fun, so they could choose to nod off into bliss if they wanted. (And probably, most civilizations could decide to be wholesale brought into the Culture on a per-person basis (i.e. giving up all their local government, culture, etc.)). It's like saying that, at the end of the day, when shit calms down, you're gonna be OK. (Unless you happen to be an unfortunate pawn... but hey, can't save everybody for some reason.)

Maybe I'm just projecting how I'd live in such a universe and that's why it makes me so happy. :\