Do you kiss your kids on the lips? I do that but have received stares from strangers and was wondering if I should stop doing it.

I kiss my boys on their cheeks and I have never initiated kisses on their lips but they love to kiss me on my lips and they are already 5 and 7! What made you think those stares are negative stares? I sometimes look at parents interacting with kids and think about my own kids, so maybe they were just looking? :)