Sitting on laps in public?

Ja
If a female sits on her boyfriend's lap in public and they are not doing anything  sexual, no suggestive body language or words, would you find is distasteful because her ass his on/ near his dick? 
This happened to my boyfriend and I today at a park (not achildren's  playground.) and awoman came up to us and told us we ought to be ashamed of ourselves to be doing sexual stuff in public where children are around.