I hear this excuse all the time from fans who refuse to hold bands accountable for some reason.
It isn't an "excuse" and has nothing to do with "holding bands accountable." Honestly, the idea of "holding bands accountable" is incredibly presumptuous and silly. I think most bands would roll their eyes and laugh at that take, and wouldn't be concerned at all about losing an album/ticket sale here and there from the random self-appointed sheriff of band accountability.
You’re telling me the fan who only knows the popular songs is more important to please and willing to buy tickets than the fan who knows every song/album inside out?
No, he isn't telling you that. Why don't you read and respond to what he actually
did tell you?
Anyway, the truth lies somewhere in the middle. Most bands are going to have a continuing list of "go to" songs that they play almost every show, and feel like they "have to" play them over and over. That's just the way it is and most of us would admit that, if we're being honest.
The other side of the coin is that a lot of fans, especially those that have stuck with a band for a long time and buy almost everything and/or go to a lot of shows, want to hear some deep cuts and some songs off of whatever new album. It can feel pretty lame when a band doesn't acknowledge that.
The real trick is finding the balance in between. Some bands barely try. Queensryche is one that comes to mind, and it's frustrating. Maiden perhaps do it better than just about anybody. But even they get criticism because you just can't please everybody. And as that applies here, yeah, I agree that playing only 2 songs off the new album is lame. If you are going to put out a new album, stand by it and play a decent portion of it. But Ben is also correct that it's perfectly understandable for a band to have a "must play" list as well, whether die hards agree with it or not.