Rider bets or over the shoulder bets

If someone is making an over the shoulder bet (rider bet) in back of you, does that draw any attention from surveillance? Good or bad for a counter? What do you do if you don't want someone riding your bets? My sister's friend who isn't a counter was playing at Foxwoods and she started cursing at the guy who was riding her bets because she started to lose afterwards. Anyone have any experiences?