Also motorway service stations are open 24 hours whereas most
non-motorway
petrol stations aren't so opening time information will have to put on
the
signs, and this would also have to be kept up-to-date.

Well, if American cousins can manage this, it would be sad if the
consensus
was that it was beyond the capabilities of the British :-(



In my somewhat limited experience, the USA example is no different than
here. They tend not to have on freeway service areas and those signs you
talk about tend to lead you to the big chains, not the mom&pop everyone is
usually so proud of.