When will people learn? In addition to Tony's comments, the petition is about parking. It might help if the petitioner at least knew the difference between parking and camping (which is what one is doing when inhabiting a vehicle).
The article is a bit disappointing in that regard as well. Whilst Nightstops and the "some car parks" mentioned operate legally that is because they comply with the 1960 Act. That is a requirement of anywhere that allows camping in a motorhome, including vineyards and farms, which the article appears not to acknowledge.
Tony is correct in that the easiest way to expand availability of places for overnight camping for motorhomes would be to relax the conditions in the 1960 Act. Rather more relevant than support from the clubs, though, would be support from motorhome owners. As I write the petition has 6,487 signatures. Compared to the number of motorhomes in the UK that is a drop in the ocean. Without significantly more support no government is going to take a petition seriously, even one which requests what it wants accurately.,
Graham