Makes a lot more sense when you put it that way. A shitty venue can make you want to bolt early for sure.
I also agree with you on liking Mastodon's earlier material more than their recent stuff (with a few exceptions for me, obviously). It seems as if their current setlists are fairly well-balanced, though, so again I would have wanted to see that.
5/18 Anaal Nathrakh (?)
5/21 MDF XIII
5/24 MastoClutch (?)