Not sure what the actual dollar qualification is. Suffice it to say that CO stars are a surprisingly small percentage of PAX that account for a surprisingly high percentage of revenue.

There's not a whole lot we can offer a CO star once on the plane. I try to address everyone in FC by name (not just CO stars) unless everyone's switched seats. If there's a CO star in main cabin (we have that info) I don't have a problem offering a free drink. Might also be nice to say "Thanks for flying with us again, we appreciate your business". Besides that, not much extra we can offer.