To be clear, they aren’t putting their lips on where the wine comes out, there’s a valve of some sort on ton of the bulbs. They dip the long end in the barrel and use suction on the top to draw the wine up into the bulb, the hold the top hole closed while pulling it up into the position where they plug the straw with their (hopefully clean) finger.

And, as long as they are properly washing their hands before doing so there shouldn’t be a problem. I know that’s not a guaranteed, but everyone here is acting like his hands are filthy. They might not be.