Adult Stores in Missouri

What is an Adult Store? What is an Adult Center? They are lined up off of I-44 in Missouri. I was with a friend on a mini trip to Springfield,MO this afternoon. We passed several of these. I wouldn't mind stopping but there is a certain amount of fear associated with their parking lot. These buildings are boarded up and there's always that old rusted S10 pickup truck parked along side. When its dark there is that one little light shining bright by the windowless door. There are no advertisements - just a bright, usually red sign that reads ADULT STORE. How do you get a job at the adult store? Word of mouth? Do they put it in the paper. These stores are in the middle of nowhere. Do you think they pay minimum wage? Do they offer insurance and 401K? I'm going to take the easy route and purchase my toys of pleasure online, or at a garage sale.