Clare thinks she might know the real reason why she was singled out for rough treatment. It's to do with her body. As well as being tall for her age, Clare is also mature. Her body is more like an adult woman's than a teenager's.
Because of that, she thinks that some of the male chaperones felt awkward about watching her so closely. If that was the case, Clare says they shouldn't have been watching so closely. She was bound to show some skin in a dress.