Yep, I've seen those too.
But those are advanced ones here in my neck of the woods. Small pickup truck campers, a blue plastic bucket, and those white, 20 gallon buckets serve as doghouses here for a lot of dog "enthusiasts."
. . . I used to work for a highway company . . . and I bet there are a lot of rednecks who've done that sort of work and wound up with chipped, cracked, or "surplus" pipe . . .
Have you seen the cat tree made of the 5 gal plastic sheetrock buckets? Held together with duct tape? LOL!
I'm glad your old Lab boy is settling in. You know he's happy to be in Sailor's Safe Harbour at last.