Why do flies arrive on the ceiling of my court when we desk light a wood BBQ? The flies are not on the food, they land on the ceiling...

The flies are not on the food, they land on the ceiling of my covered patio every time we wishy-washy the wood-burning BBQ. Are they just hanging around until the food is organized and off the fire? Are they attracted by the grease?
Answers:    Grease Vapor is sticking to your ceiling ,and they enjoy this outstandingly much.They wont lay any eggs since its on the ceiling,and not enough to raise a poor lil maggot.
Its non-hazardous for the most part,but a little bleach up nearby would solve this problem.
Of coarse there better off up at hand then on your food.
Hmmmmm desicions desicions
They are doing the same item as your neighbor does, but your neighbor doesn't land on the ceiling...he hangs on your paling...both hoping for an invite. good way to smoke them right out...they are discouraging