I will occasionally take a sleep aid while on the trail. I can have problems sleeping the first few nights of a trip. I use a low dose benzodiazepine and have no difficulty waking in the morning. So, yes, I have "encountered this". Do I think it is "cheating"? No, no more than I think taking ibuprofen for muscle aches is cheating. Moreover, let me suggest that it is probably not really appropriate for one to judge how another person deals with sleep-related issues. In other words, HYOH.