I don't talk much or yell, so when I talk allot or yell, my throat gets sore. I think if you do it more and more, your muscles get strong and you can do it all the time, like those rock singers. But, you have to break into it slowly, just like exercising for anything else.
Yes. It may not take a lot of yelling, either. For some people they can yell all day long and not get hurt, but for others if they only yell for a couple of minutes they'll lose their voice the next day.