2 things (initially)
1: so they make cold calling illegal, fine. but who will police it? the merseyside police??? because then we'd have umpteen threads on here about the police not catching other criminals and instead driving round looking for cold callers. it's an unenforceable law and as such will never be passed.
2: yo umake it sound that all travellers are bandits, they're not, i've met a fair few and i have to say nearly all of them have been nice and honest people. some travelling communities are different to others i accept but that's in the same way that African tribes differ from each other. it's what they're taught, so if a travelling community has been doing so for say 150 years then the original group have died and there are at least 3 generations below who mould the behaviours in a way they see fit. so if the original founders say "take only scrap metal that has been clearly abandoned and only contact people seeking work" then later generations may twist that to mean "take all metal that has been left and knock round people and see if they need work doing" very much in the same way that the Catholic religion isn't now what it was 1500 years ago, same as the Muslim one and Sikh and the such. the longer things go on for, the more the generations play 'chinese whispers'
i'm not saying every traveller is a angel, but not every human is an angel either.
your blatant judgement and borderline racism scares me and i hope to god you sort it out