Hussar
Legend
It is not about not letting ppl shine it is about trivializing a challenge.
Everything gets easier at higher levels, and yes in DS managing water supply should always be an issue, even if that means killing dinosaurs to drink their blood every now and then.
But, that's the thing. If you kill a large creature, for example, food stops being an issue for quite a long time. Figure something big, say, about a ton. That's enough food for the party for weeks, presuming they spend the time curing it and whatnot. And it's not like big critters are all that rare. So, does it really matter that much if one PC doesn't need to eat? The rest of the party still does.
It's like having a flying PC. Sure, that PC can do stuff that other PC's can't. But, at the end of the day, it doesn't matter that the PC can fly if everyone else is walking. You still need to climb that cliff, make a boat to sail over that river, whatever.
Now, a PC that could make food and water for everyone? Sure, that's a problem. But, one that isn't terribly concerned with weapons, but, instead has unarmed attacks? Considering Dark Sun has Thri-Kreen which come equipped with natural attacks, I'm not seeing how a monk is that big of a deal.
Or, put it another way. If the challenges of your campaign are that easy to get around, perhaps that isn't as much of a challenge as you think.