@Inna22 If the towels are in the bathroom, how much more obvious could you be? Unless they're hidden, or your bathroom is 1000 sq. ft or something, I cannot understand how someone can't notice towels.
I have two towel racks right beside the shower. Each rack contains a bath towel and a hand towel. I also have 4 extra bath towels in a cabinet under the sink with a framed note on the counter than extra supplies are in the cabinet.
Interestingly enough, I've had several guests forgo the towels on the rack and use the towels under the cabinet. I guess they thought the towels on the rack were just for show. LOL!
Maybe this is a cultural thing, but it's common sense for me to look for/find towels on a shelf, rack, or cabinet in the bathroom. If you're too lazy to look, well, that's a different story!