'This thread alone is clear evidence of why traveller communities should be discouraged anywhere.'
Well...I wouldn't go that far! They do have to live somewhere, after all. But we should be tougher about stamping out illegal encampments much earlier on, before they get anything like Dale Farm proportions.
Perhaps we should have far more regulated legal stopping sites, actually run and managed by the councils, rather than by Travellers themselves on behalf of the council which is what tends to happen now I believe. That way it is easier to nip abuses of the system in the bud before they get out of hand. the sites could be run to strict guidelines with wardens etc, just like holiday campsites are.
The sites should much more numerous (a minimum number in every county) but always kept small to reduce the ghetto effect, and so the impact on the local settled community is not such a negative one. They should be in areas that blight as few privately owned residences as possible, if they are to ever gain wider acceptance. There should be strictly enforced limits on the amount of time people are allowed to stay before they must move on. They should be available to any supposedly nomadic community, Roma, Romany, New Age, not just Irish Travellers. If they don't like that, tough. We do not live in an apartheid state.
The trouble is, Travellers these days don't actually want to travel regularly as itinerant workers, but merely want their own private gated community, full of hand-picked friends and neighbours and free from people we prefer not to mix with (and don't we all? 
) at a tiny fraction of the cost that the rest of us would expect to pay, even if we COULD demand such a thing. Therefore there can never be enough legal stopping sites, because no-one will bother actually giving up their legal pitch. They'll just put a static bungalow on it, and go off on long jaunts in their travelling caravan, but keep their permanent home as well, so it defeats the object. They cannot have it all their own way. If they want to use their 'travelling' heritage as a reason for special treatment then they need to actually travel, or it all becomes a bit pointless!
Any Traveller who wants to live on land he owns, and/or build permanent residental structures on it should be absolutely MADE to comply with planning regs and there should be a zero tolerance approach to flouting the law in this regard. But the only way we can do this at the earliest opportunity is to prove that there are sufficient legal sites for them to stop at, so they cannot use the 'nowhere else to go' argument. Whether they want to stop there or not, is not really any of our concern. Like someone said upthread, anyone else requiring state funded/subsidised housing does not get to be nearly so picky at the taxpayer's expense.