Greedy my A**
He has the right to be paid for the use of his image/likeness/voice etc.
He is “selling” that product and deserves a commission.
According to the yogurt company, they bought the image from a photo marketer who had the legal rights to the image. If the marketer didn't, then he needs to sue the marketer - not the yogurt company (provided the yogurt company quits using the image thereafter).