Wow. Okay.
In strong addition to what Kaydeejayde said:
1) They are NOT disgusting. These people are NOT going around snorting norovirus to burst out on stage as a publicity act!!
2) How can Rod Stewart be compared on any caliber to Gaga and Bieber? He's not even the same genre of artist! And using Rod Stewart as an example leads me to believe (or assume, like you're always so happy to do but this makes more sense than your assumptions) that you weren't going to pop concerts, or rock concerts. Not because those are where the "druggies and drunks" perform, but because that's just where you find a more intense show. and to do those types of shows continiously?
Do you understand that both artists (Gaga and Bieber) are in the middle of intense tours? After doing intense tours? Doing a HUGE show every single night? Exhaustion can make the body act in different ways. I say that because even I got sick from being exhausted and then overworking myself at the gym! Good god. So to answer your question is that today's "generation of pop stars" have to oblige to a bit more of a demanding schedule, routine, etc. I sure as hell give them credit. I could never do anything like that, and Hairyfairy, neither could you. and I bet if you did? your body would become tired, and overworked, and it can make you sick. Surprise! You're human!
3) You blatently said you're assuming. So your entire "point" is based off of just how you feel it is, rather than looking at the facts, that have been mentioned in this thread countless times.
I apologize if I repeated myself but that was so annoying to read.