There’s references to all sorts of real-world sh*t in there. The ones that jump to mind are:
Stonehenge – I think it was Sabbath that had to leave a mammoth piece of expensive scenery in the warehouse since it wouldn’t fit on the stages of the venues they were by then playing, their appeal having become more “selective” at that point. The Spinal Tap skit was the converse, of course.
The foldy up mini sandwich thing – calls to mind the Van Halen blue M&Ms thing (which turns out to have actually been quite clever (there’s a fine line…) when you know the full story
The bit where they meet the guy in the hotel lobby who once supported them but it is now massive (“they were still booing him when we were playing”) also calls to mind an exhausted and declining Sabbath who were blown off stage by an up-and-coming Van Halen supporting them.