I disagree. Why on earth should he take personal offence if you say something about the company. I told a mate who works at tesco I think it's horrible how they put smaller business out of competition, guess what? We're still mates, he laughed and agreed, but what can you do?
Criticism of his store, however is a different thing, but still, he should have asked why the OP felt that way, and could have disagreed, corrected and took on board any genuine criticism. I know he'd have to be incredibly patient to do all 3, but a small example "Yar, don't like the way it's run anymore, we cant game on saturdays

" reply "Oh really? that ..... was a one off, you're more than welcome to come down most saturdays and game. Hell, bring a friend, its a bit quiet at the moment and we miss you." to which the OP could say "Oh, awesome, cheers." or "I dont know, but I'll see what people are up to."
As it is, it went more like this:
"Hai hater, y u no lyke us no more?"
"reasons, blah blah blah, mentions store and company, fairly civil tone."
"wtf, thou shalt not offend GEE DUBZ gaarrrggghhh".
If I was the OP, I really wouldnt be worried about some comments off a guy on £12k a year :/