I seem to have developed a "look" though it was getting ridiculous in the city centre, like running the gauntlet between them, street vendors, beggars, Big Issue sellers, free papers, survey people, preachers, non-chugger charity people.....
Chuggers re now restricted to certain parts of the main shopping street (both ends so you're safe in the middle) and some other areas and only one lot at a time, restricted numbers etc...
Makes them a little easier to avoid though I have resorted to having to be quite rude on occasions and usually front out asking them if they are being paid (which, of course, they are) and make a point that I object on that basis and that if I want to give I will do so directly.