I've never met a climber who calls their crash pad a climbing mattress. The poster said he bought it for hiking. I could be wrong but figured I'd post it here for the community.
If I recall, there was a guy on here or the taco that had lost a mad rock pad out the back of his truck while driving not to long ago. I wonder if it's the same one (in which case it isn't stolen, but found). Maybe some remembers that post and can give him a heads up..