Outlaw,
A tinker is the name of folks who began in Ireland. There are a lot of stories about how they began. They did begin as itinerate groups. They've been around for centuries, some say. Some say the Famine years made them grow.
I stayed for a day with a small group in their wagons at the side of the road near Limerick when i took a messenger boy's bike across from Dublin wandering toward Galway that spring after the beggar episode.
I had a stretch of time off while the College of Art and Design was on break. (I finally got money working as an art model) The tinkers had horse drawn caravans then (I don't know about now) they spoke no English I could understand but "smokes" or something like it--they wanted me to pedal to the local news agent for cigarettes for us all. I smoked then.
In the country, they had a separate world from settled folks in the towns. The children I saw in the camp were like wild rabbits. You can find pictures of them on the net. Sometimes they are called the travellers.
But they do/did settle in Dublin and some(at least true for a tinker boy who i got to know slightly)return to the country in the spring.
there is pretty much a "we vs. them" attitude between tinkers/travellers. They are fringe dwellers by necessity and choice.
There are stereotypes of them. The kid who I knew was one I went to when my purse was stolen. He couldn't break through to help me, though. I only wanted my bag back (couln't easily buy another) even if I hadn't lost anything of value in it. He knew who had taken it.
Beggars sometimes just see others as a "mark". Nothing personal in it--the havenot may make stereotypes of anyone with a penny more than they have.
No one likes feeling like an object, either way. City tinkers were a little more "prejudiced" in my experience than the families I found that spring. But I don't know it all.