How about lobbying some of the large supermarkets to offer an area for MHs in their huge car parks for one night stop-overs? There could be a section, with water & waste area for a few MHs, the car parks are empty at night anyway and they could insist there is a 'minimun spend' of say £5 or £10 in the shop, just produce the reciept and get a token to put on windscreen. There are a zillion s/markets all over the UK, with big empty car parks, some very central locations too! Most have some sort of security, like CCTV. Stand a better chance with them, than the councils I would have thought.