"Starbucks Squatters"....lol at that!

I went on a rant and didn't answer. First of all, if I'm eating and almost done and see someone holding a tray and waiting, I just finish up quickly and get up. That's common decency to me. If I had just a coffee and they had a meal, I would also get up because I can drink and walk.
Not everyone will do that, I notice...

If someone wasn't eating or drinking, hmmmm. I would LIKE to say that I would ask, but I simply don't think I would (or it depends on how gutsy I feel that day, idk). I might lurk within their field of vision and hope they learned some etiquette...

Also it depends on if they're elderly or don't look well...then I would wait for someone else to move.

Mostly though, for me I guess it's just as rude to go up to a stranger and ASK them to move, as it is for that stranger not to take the initiative to move on their own.