I think the point was more that shopping containers limit what you can build/create, since it's a small space to work with. The marquees back over by the hotels a few years back offered more creativity with sets.
Although of course now they have the Towers of which there is plenty of space to play with anyway (The Sanctuary really shown that off with some scenes).
I find while the current set up is easier for Towers, there's still that atmosphere that can't be recreated like the one you would have gotten over by the hotels a few years ago. Queueing for Boiler House/Carnival at 11:30pm in 2010, on an empty field, with just creepy Toyland Tours music and screams being heard in the background... that's an experience like no other, and it's a shame that everything's confined to the theme park these days.
Not to be too much of a moaner though.
As long as the mazes are good on the inside that's all I care about these days. External atmosphere is just a nice bonus.