At the risk of chucking paraffin on the flames...
There is a *very* good reason why the majority of the regular contributors to THBF range from cold towards to anti mass produced commercial beer (not just lager I hasten to add) is because, at the "really do it all yourself, spend a whole day making a beer" end of craft brewing, the people involved are the people who have done enough drinking and learning to grasp the basic concept of the mass brewer which doesn't fit with their ethos when it comes to produce.
Mass producers do produce good stuff. But on the whole they don't. They are tied not to out and out profit (as is the common misconception) but to continuity and uniformity (because that's what investors like) and mass market appeal gives you that foundation. They cannot be radical, they cannot break moulds, they cannot put themselves out there because investors get jittery. So they have to produce mass market stuff and compete only on marketing for market share.
It stifles innovation at the product level (but drives it very hard at the marketing level) and that's not what craft beer is about.
Which brings me neatly back round to where I started. Even if (and some of them do) the mass producers made really tasty beer, there would still be a large "anti" feeling because it would never move the product on. It would be tasty, but there it would stop.
Grolsch? Not for me thanks. I'll spend my hard-earned on a 77, a Cotswold 3.8 or a Scheihallion instead. I think they taste better and and it supports the little guys (although I'm finding it harder and harder to call Brewdog a little guy nowadays...).
Anyway, the point is, just like food, I like to know that my beer is made by people who care about the beer first and the shareholders second.
I suspect this is from where what you call the "stinking attitude" comes.
That and the fact that you asked the question canvassing peoples opinion of Grolsch, you got them from a representative sample of the UK's home craft brewers. It's not a case of having just mentioned it and been hounded for it, I'd take a different stance if that were the case. It's not cool to ask for people's opinions then get funny about it when they give them. Sorry.