I just went and watched a hive entrance to see if I could see this behavior. What I saw was that around 60% of the bees seemed to run and fly straight out of the entrance- whilst a smaller number did seem to pause for a split second and touch their faces. I have no idea why- I guess it could be as you say- that they are adjusting checking their eyes before flight. I wonder also if there is some small adjustment happening as they go from the dark of the hive into the light?
Being creatures that fly like birds- it wouldn’t surprise me that they preen and clean their equipment before flying to make sure there are no issues. Birds spend a lot of time preening and adjusting their feathers for flight worthiness.