Nobody leaves with images on cards...
That is, you have a fast 'puter with a CD burner and a card reader and you off load all images on all cards into the computer. Burn a CD for the photographer, sort the images by models, and burn CD's for the models. Everybody goes home with images.
Yes, some shooters will scream "But they're not edited!!!" All the more reason for the photographer to get home, edit, and send the model another CD she can actually use.
If the photographer flakes, she still has raw images and all's fair in love and ...er... shooting and modeling.
Film shooters? Dinosaurs, soon to be extinct...
But I am a dilettante so whaddo I know... You say this doesn't work... Why not?