I know about the camping supplies limit in your inventory, and how it varies depending on your difficulty settings. But I haven't been able to find out if there's actually a finite amount of camping supplies in the game.

Do the merchants ever restock or is there an option in the stronghold that provides you with supplies? I play on normal, so I'm nowhere near running out, which makes my question super hypothetical. But still; could you theoretically buy and use up all the camping supplies in the game?

I am 90% sure the merchants restock. my big question is where can I find free ones. I am cheap. 

Merchants restock

they definitely restock, just ticks me off when they sell 3 (or less)