Was this an overreaction or a correct gut instinct?

Long story short, my husband had to use the restroom at the airport the other day.

Well he was in the stall doing his business and another man stuck his hand under the stall and was wiggling his fingers for a while, close to touching my husbands leg.

My husband was freaked out and didn’t say anything in the stall, but he followed the guy back to his seat, and told him he was sick and he needs to keep his hands to himself in the bathroom.

My husband thinks he was a pervert and said the only reason he got so upset was the thought of it being a child in the stall instead of him.

Just curious if anyone has dealt with anything similar?

Is this like a thing people do to try and touch children? I googled it and found nothing.