I have not noticed anything like this on cars, but bicycles is another thing altogether.
Because cyclists are a danger to everyone around them most of the time and blame it all on motor vehicle drivers, some have rear lights which flash on/off to attract attention when you are approaching them from behind.
This is all very well, but I have noticed on a couple of occasions when getting close to these guys in the dark, it is very difficult to actually focus your eyes on them to try and avoid running in to them, all because of these stupid damned flashing lights.
JimB