It never ceases to amaze me the lengths that cyclists will go to to justify breaking the law - and endangering themselves in the process - even to the extent of condoning the non-use of lights by cars!
Blaming the car for driving without consideration from your hospital bed or your grave is a pretty stupid way of making your point. I'm "lit up like Blackpool" and ride on the assumption that every other road user is an idiot who hasn't seen me. I drive my car in the same way. If a motorist does hit me they, will have no excuse whatsoever.
Cyclists are road users and the law is clear. Aside from that, lights are safe. Just switch them on and be done with it.
On that note, I'm concerned by the number of early morning cycle commuters in Bristol who are not bothering with their lights - sensible, hi-viz wearing, helmeted commuters with lighting already attached to their bike. The cars have their lights on because the sun is low and the light is dim. That's a pretty clear sign that you need to do the same.