Cold approaching is annoying but fine, It's just inappropriate in most places, the grocery store is a hard no. Gym is mainly a no, especially when you semi stalk a girl from machine to machine, at least get some eye contact and a smile first. Don't follow women on the street, and absolutely not in your car if she's walking. Really there are bars and clubs for this and online dating so I thought this behavior would be curtailed.
Cold approach is annoying if they consider you ugly
There's no inappropriate place to bag a Women if you come with respect.