So... you get room service? Like... how far do these workers stay from these rooms? Can they see you pee and take a dump? Where do you clean yourself? Do you get a refund if it rains? Is a simple hotel room somewhere nearby cheaper than this gourmet outdoor experience?
The beds are outside in the countryside, usually on fields that are owned by the farmers who offer the "rooms", so they're a bit secluded.
You're brought there by said farmer, he shows you around a bit, shows the fridge, etc. Then he leaves again.
If you need any room service, you just call up the farmer and he comes back to bring it.
No idea about toilets, but I think you'd also have to walk back to the farm. Same if it rains. Pretty much all of those openair hotels are ran by those kinds of farmers anyway, who were used to hotel guests as they've been offering "sleeping in the hey" kinda things since years, so for them, it's pretty much the same, except being a little (sometimes a lot) further away and being logistically a bit more challenging.