It's a simplified interface designed for phone browsers. I'm not entirely sure, but I think even with "never" checked, you may still end up there for example if you follow a search result in Google to FlyerTalk (sometimes Google indexes the mobile version of a page instead of the full one) -- there may be other ways this can happen, but that's one of them.

In particular mobile skin forces infinite/continuous scroll, which you mentioned, hence my curiosity. If this is indeed the problem, it's trivial to fix per the instructions in the other thread. If not, then your guess is as good as mine :-/