I couldn't imagine that also the LARS units coordinate with each other for a VFR flight
It's happened to me. Not very often.
Biggin instructs 'freecall Farnborough radar': I contact Farnborough ...
You can if you like. But if you don't want to talk to them, or if you don't want to talk to anyone at all, you don't need to - they aren't expecting your call so won't take any search and rescue action if you don't call them. (Assuming OCAS.)