It would be great, I agree, but unlikely at the time of economic recession.
Put it this way, is it better to have more cuts in health and education and spend money on aires, or vice versa? At a time when people's jobs are on the line in a very real way it's a leisure item which will not be at the top of the spending list.
The other thing that has to be considered is the existing infrastucture and provisions. It's a different model to France for various reasons. In the UK, there are many CL's and CSs, small 5 van sites at farms etc that have invested in things like electric hook ups, hard-standing or access roads. If a person owned a CL and had just spent £3000 putting in hook ups, would they be very happy if the Council started spending their council tax building aires in the locality resulting in them going out of business?