Ok, people, it's not that hard: a good *B movie* has tits and blood, a general good *movie* has other things. Simplifying other's opinion in order to disagree with them makes you look dumb.
You did the same thing with The Expendables. He describes the "probably worst kind of person" (basically those that don't like action flicks' key improvements from the last decade) and adds that those people "will probably like this [The Expendables]". You might not want to realize it, but that's different from outright saying "People who like The Expendables are the worst kind of person". Get your facts right.
Now, about the sheep part, if you paid for The Expendables out of hype (you shouldn't have), then yeah, group mentality. He's right. If you waited for comments and reviews, made up your own mind in an informed fashion, and then went to see it, good for you. After that, liking it is just a matter of taste. Supporting the hype machine that sells you crap you don't want because you're too lazy to think for yourself is being a sheep. If you're insulted by this, you deserve it, but probably you're not smart enought to understand, so you'll keep whining. Luckily smart people won't care about your whining. Bob didn't.