"The dale Farm piss takers are Irish tinkers. Ethnically they are the same as any Irish and many British people."
You are right that they are different from Romany gypsies but if you read the stuff here
http://www.bbc.co.uk/news/uk-15020118
Talking about the Irish travellers and the gypsies
"We're two separate ethnic groups. Whilst there is some conflict because people inhabit the same social and physical space, there is some kind of harmony; some inter-marry and live alongside each other. Both Irish Travellers and Romany Gypsies are recognised as distinct ethnic minority groups in English law because they are communities which share a history stretching back hundreds of years. The term traveller refers to anyone who has a nomadic way of life. It can not only refer to Irish Travellers or Romany Gypsies, but also those who live on the road for economic reasons such as New Travellers or Showmen. There isn't one Gypsy and traveller culture, just as there isn't one single Gypsy and traveller community, However, the way of life of living on the road means that there are "certain cultural things in common",
So I guess that is why Irish travellers and Romany gypsies get lumped together.
CHeers
D