If the engine is going to be started then the anti-collision lights have to be on. I am sure that we all agree that a red flashing beacon is ideal but what if you dont have the option.
I have been asked to turn my strobes off (at night) which leaves me with no anti-colls on. IF I had a collision what do you reckon my insurer would say?
I dont even like landing with them on - ground reflections can be a proper pain - but it is unfortunately law. If people want to take the liability for me turning them off - or pay to have a red rotating beacon fitted then fine - otherwise its tough.