Yep, these have been relisted on eBay every once in awhile since about October. Aesthetically, the composition of these customs actually look pretty cool, especially the Mantle (ie. the framing works with the size).
When? Probably in the mid 50s to early 60s, when baseball cards from this era didn't really have a lot of monetary value.
Where? Probably in some 11 year old's bedroom.
Why? The kid might've already had a complete 1950 Bowman set and wanted to add these so he cut them to fit in with the others? It's hard to tell, but based on the who, when, and where, there probably wasn't much thought put into it.
When you break it all down, they really are just little pieces of old cardboard.