This is a really valid complaint, and it’s weird that I like Dominion anyway since this is my main problem with nearly every Euro game every developed.
But with Dominion, I kind of feel like Phileas Fogg sitting around playing whist with his gentlemen cronies. Once everyone gets comfortable with the game, it goes very quickly, with most turns taking just long enough for a player to say, “market, market, whatever, whatever, eight gold, buying a province.”
And then everyone nods approvingly, somebody says “jolly good show, chap” and adjusts his monocle, and the game keeps going.