On his rice burner "chopper" it looks like he didn't have enough stock to fabricate a new tank, so he just welded on scraps to an exsisting tank.
Either his scrap pieces were small, or the only way he knows how to cut sheet metal is in rectangles.. that would account for the "frankenstein" welds.
My guess is this guy collects old parts and junk for free (or next to it) and slaps it together as a hobby.. selling stuff on eBay to help replenish the "tinker fund".
I think i'm going to try and find an old AMC Gremlin, rip the front clip off, weld a chunk of shopping cart to the front of it, and see if I can sell it for 2 grand!