I'll turn mine off when the videographers turn their annoying deer lights off... (i.e. it won't happen).
It's professional to be able to get the shots we need to satisfy the client. The cameras we use focus more quickly and accurately with the AF assist. I, for one, can't see myself going to a bride after a wedding and saying , "Sorry I missed that once-in-a-lifetime inverted triple lutz leading into an aerial kiss during your first dance because my camera couldn't focus...but at least your video dude got it!"
And the video lights that videographers use mess up my exposures. But you know what, I adapt and I deal. I change my exposure to compensate for his/her lights. That's part of being professional. All the videographer has to do is shoot a different angle than me and he won't see the red web I'm casting...that's the professional thing for him/her to do!
Sorry if this sounds a little harsh, but I hate it when another vendor who's not a photographer, tries to tell me what is professional. That would be like you telling the DJ that the florist told you the "fact" that he's not professional if he uses a laptop instead of a dual CD deck