From what I understandin the UK at least there are some outside aviation that would like a VFR plan submitted for every flight.
But really the UK ATC system isn't interested or setup for doing anything meaningful with them.
Also as well I suspect alot of flights don't really have an objective in that yes you may set out to a destination but may go somewhere else in the end. I suspect most pilots who start out doing the good thing and do this once and have to deal with all the fall out then don't bother again.
Take a trip from the South Middle England up to say Wick VFR. Unless its CAVOK over the whole of scotland I won't have a clue which way I am going until I get near Perth depending on the WX. It will either be straight over the top, up the A9 or round the east coast. Over terrian which you would be well advised to have a flight plan in for, for SAR purposes. All I do is not bother with a flight plan and make sure that scottish Info has my routing and ETA for the next major turning point and who I expect to be speaking to. Its not perfect but I would hope it would work.
They do phone up and check, when ever I have asked the next ATC to give them a ring and let them know, they have nearly always already phoned to confirm we are safe.