Crazy people on bikes come out at night, too

A friend of mine works the night shift at one of those 24-hour big box gourmet supermarkets. EVERY night around 2am, a woman rides up on her bike. The bike has a big basket on the back and front. She shuffles through the store, mumbling nonsense to herself and picks items to buy. She'll buy things like one banana, a small quantity of nuts from the bulk bins (like 10 or 12), maybe half cup of oatmeal, etc. One time she got into a fit with the night manager because she only wanted to buy one aspirin, not the whole bottle. So he just gave her an aspirin from their first aid kit. Her purchase never amounts to more than $5 or so. And this goes on every night....