On a camp site only accessible on foot
On a camp site only accessible on foot
Went to a camping in the Laurentians in Québec (Ste-Agathe) and there were those things near some camp sites. The sites are only accessible by footpaths. No car access. And if you bring a bike, you have to walk it up a hill, so I doubt they are bike racks.
EDIT: I have sent an email to the park and they have been kind enough to reply. It's just a type of fireplace with a grate. They didn't give more info than just this. Thanks to everyone for pitching in!

looks like a grill to me.
The concrete isn't discolored like it would be for a grill.
Maybe everyone else who has ever been there was just as confused as OP, and never realised it's a grill, so it's a grill that just hasn't ever been used.
Could it be a grill that hasn't been used in a long time? It really looks like a grill, but I'm confused in that there is an obvious circle-of-rocks firepit clearly visible in the bacground.
I would second this guess.
If not a grill, could be a good work surface for a pot or pan