Always, always wear clothes to the interview. People say the first thing they look at is your attitude, but it's always whether you're wearing clothes or not. On a personal note, I recently applied to a gas station, the guy wanted me to stand out by the pump, clean peoples windows for them, and help them pump their gas if necessary. My thinking is, if you can't pump your own goddamn gas, you shouldn't be driving anyway. Needless to say, I didn't take that job. But, you should always wear clothes. That's important.