It's not odd, That fuse block is cheesy in that it can't take abuse.
I think careless removal of fuse block relays introduces gremlins
by opening up the spade lugs (relay socket pins). There should be a simple
tool to pull them straight up.

You can't replace individual relay sockets at the fuse block.
You can remove each socket pin, which is simply a wire with a spade lug
crimped on.

I'd still like a source for replacement spade lugs with the lock tabs.

Bill