Unless you are talking about something different, formal mentoring to me is just working with one person on a particular aspect of life improvement. You may have a financial advisor, or someone assisting you in building a business, or someone skilled in organization skills improving yours.
We often use these for kids that are behind in school, tutors we call them, one on one instruction.
Informal mentoring is what we receive in classroom settings, listening to learning audio tapes, CDs, DVDs, reading books, in church or even at this forum.
I can't tell you what seems false about formal mentoring, I know there are a ton of mentor programs popping up, folks going thru some sort of class to become 'certified' yet haven't got their own lives together yet, I'm going to pay them to help them with mine? not.
However there are tons of retirees and well to do folks that are willing to provide assistance utilizing their life experience.