I cannot think of an example exactly like that. But in many professions, senior members are the ones who certify junior members. Law, medicine, all the reputable parts of finance.

I mean, to make my actual argument, instead of just alluding to it, it seems to me that:

1) it's good for consumers of an industry to have ratings of the providers in that industry

2) I can think of three sources for such ratings: crowd-sourced ex-customer ratings, ratings by a purported expert-at-rating, ratings by peers. I think these each have their merits.

3) If ratings-by-peers is indeed useful, then in a given industry, it has to start somewhere.