It all depends on the context I suppose.

Ten years ago I was on holiday in Europe and the gondoliers in Venice flirted with all the girls on the bridges we went under.  The girls flirted back just as hard.  Obviously nothing was actually going to happen, and it was all treated as just a bit of fun by everyone.

Making obscene gestures at work, on the other hand, needs to be dealt with by the HR dept or similar.

Karen.