Since you know so much about the bezness culture. Why not get the hotels to write a warning to tourists regarding love rats. Only travel agencies or hotels can warn but of course they will lose money and that is not good for Tunisia.
That idea crossed my mind, and I've tried .. but it's not as easy as it seems honestly ...
Warning people of Bezness guys, is not a warning that could be written on a piece of paper and hanged on the wall, because people will need explanation, second, it could considered a discrimination as well .. In Paris for example, you don't really find hotels warning of Scammers, despite the fact that these scammers (NGO's and signature scammers) are all over Paris.
But Love Rats, I consider this an Organized crime, so it's very difficult to warn people with a paper, otherwise you'd find yourself acting like a paranoid all over the city and the hotel, and this results that we can't get to enjoy our holidays as we'd spend most of it watching over our shoulders and expecting the worst out of everyone...
For Travel agencies, I happen to have noticed few times during my trips back home, that some of the guides tend to warn Tourists of these Rats, all the time.
I guess the only way to warn of such things is through advice, social media, forums etc.. this works better in my opinion.