Strange that the Amiga version has pure black backgrounds. Ocean software = scumbags
If memory serves Adams Family was ported from the SNES version, which had some nice parallax backgrounds visible where the black holes are in the Amiga incarnation. I suspect Ocean originally planned to port the parallax scrolling to the Amiga too but decided late in the day it wasn't fast enough and then didn't have time to do anything else instead. The ST never had a chance of pulling it off (cf its dismal Shadow Of The Beast port) so detailed non-parallax backgrounds were included in the design from the start.