Confuses me even if you add the apostrophe ;)

Carson sends in this photo:

While stopping at a restroom in southern New Mexico, near Socorro, we saw this abuse. We had a Sharpie and thought about fixing the sign.

Can anyone tell me what “Dogs’ Restrooms” would even be? A roll of plastic poo bags?
Or is this sign simply advertising a stop where dogs are present and restrooms are available?

No RV’S

Flossie sends in…

The really sad thing about this sign is that it’s at the entrance of the parking lot for my university’s main library and English department building–so you know a lot of librarians and English professors are slowly going nuts from having to see this every day.