Legislation and enforcement are seldom the correct answer...
In particular, this sounds vague enough to be nearly impossible to enforce...and probably no new law is necessary, since there are undoubtedly laws against assault and harassment already.
It is perfectly possible to 'insult' someone while using perfectly innocent words in the correct tone of voice, or with the correct expression.
Politeness in society is not enforceable by law, as it is primarily learned by custom, and varies from place to place even within a society.
Rudeness, per se, says far more about the character (or lack thereof) of the speaker than of the listener.
If I were her, I would continue to record video, ask the 'gentlemen' their names, and file civil actions against them. The usual response to rude comments is to fling an equally rude comment at the source.
"Hey, baby, how much to have sex with you?" Rude guy.
"For you? Even if you could get it up, which I doubt, you can't afford me."
"Where do you live baby?" says Mr. Nobody.
" " (Print it on a card....)
"" Rud E.
"Does your mother let you talk like that?" or "Does your wife know you're loose?"
"What do you say to a little ^&%&?" Little &*^&.
"Goodby, tiny."
If they are actually physically following you, this is a threatening move and in most places can be prosecuted as assault....of course, the judicial system has to agree, and many judges around the world are just as bad as these guys.
And of course, a proper kick in the pelvic girdle will break the pelvis, leaving them to crawl home in intense pain....
It's a sad statement of our times that the only solution governments can come to for such a problem is to legislate against it--far too many politicians seem to think that simply passing a law actually changes anything. In fact, the police on the beat have far too many laws to enforce already, and thus only selectively enforce what they feel makes the most sense.
Financial fines are not very effective, far better to reinstall public stocks and sentence them to a day or two of being publicly ridiculed, putting them on the media with their crimes. A day's lost wages combined with public humiliation is far more effective than a few Euros.
When it comes to enforcing politeness, social ostracism is second only to armed response in effectivenes.
