They probably get paid a little. As for the clothes, it is not live. They film it all in one day, then just break it up into episodes and run it. Of course, if would be smart to have the kids change clothes between people, but the fact that they always wear the same clothes helps people who watch the show remember who is who. This is because, as you may have already discovered, 99% of america is not smarter then a 5th grader. and the 1% that is, ARE 5th graders.