Then there are 'all the other' ways:
Votes based on overall looks, popularity, success of last movie or song, taste in shoes, taste in clothes, who they're dating or married to (this week), how they act in their public or private lives, their chosen profession, wild guesses, alcohol or drug-induced whims, and maybe worst of all... 'trolling' by voting down any celeb but their 'favorites' to keep those higher-rated.
That's why I rate (using the *first* method listed above), and then don't pay much attention or even care what their 'overall' rating is. Because I know I'm always right!
You asked! Some people rate the feet based on their own opinions, preferences and tastes after a careful examination of several pictures, preferably barefoot or in flip-flops or sandals.