Re the poo questions: Travellers would not bag up their poo like humans do with dog poo. Firstly they are not dogs but people so to liken them to animals would be seen as very offensive and b. Where would they put the poo? It's not as if a large encampment would all put human faeces in overflowing dog bins even if you got over the factor of likening them to dogs plus this would be very hazardous for waste collectors to dispose of because of human to human transmissible germs.
This beggars belief, I'm sorry. It in no way likens travelers to dogs to insist that sanitary waste is disposed of safely. Any sort of rudimentary bin (can be bought for about £10) to put bagged waste in, would be easier to dispose of than the scattered faeces, sanitary towels, nappies and toilet paper. Disposing of waste in a fashion that makes it less hazardous for the general public has to be a consideration if there is to be any sort of negotiating for legal stopping sites.
Likewise it's not really practicable to carry round a spade and dig a hole when you have many children running around and little time because you don't want to be caught by anyone pants down having a poo. Speed is of the essence.
Sorry, but I have seen kids running around sites without adults, and digging a hole to crap in doesn't have to done with your pants round your ankles, i have done it myself - it doesn't take long!
If there were toilets, Travellers would use them. It is unfortunate that there are so few legal places to stop with facilities which mean when Travellers stop illegally there are no flushing loos.
When a group of travellers, parked up in a sports facility that my dh used to work in, dh and the manager decided the best way to deal with any potential problems was to open the facility toilets - the turnstiles were still used (at least they could be hosed down!) as was the goal (I don't think they were fans of the local team).
It is unpleasant but the most sanitary and cheapest way for councils to deal with human waste is to simply leave it if it is spread thinly and not in large concentrations to degrade naturally over a week or so. If there is a larger toilet area with higher concentrations it is sprayed with disinfectant and left.
The school that my dh works in had to pay themselves to have it cleared (it is a private school), it cost about £5000, and meant the sports fields were unusable for weeks, nearly a whole term. My dh was still coming across waste in verges after the clear up. Honestly, strimming through a pile of crap is grim, they had to wear full protective clothing and masks, because it sprays up in the face.
Yes, legal stopping sites would be great, with facilities, and I am sure that these would be used by the majority. I do think that there would still be groups that would refuse to park up in the legal sites (as was the case when we had to move). If, as Twosides says, there is such fear of settled society, surely there would also be fear that moving into council run sites would involve their children having to attend school etc? I guess in the past farmers would let their land be used, for temporary encampments, but I can't see that happening now.