This is a multi-level marketing sort of thing -- no matter what job you apply to, what you'll actually be doing is direct marketing (standing on a street corner trying to sell things, or sometimes going to every business in a certain zipcode to sell cable packages).
The basic idea is that you work very very hard for them for awhile, and someday they'll help you get others to work very very hard for you. The people I shadowed for my interview were very friendly and engaging -- i.e., very good at marketing themselves to the real client, the person on the ladder below them.
I would recommend against working here unless you enjoy doing 10 hours a day, 6 days a week, working commission so one day you can take a cut of someone else's commission. That may be the dream for some people, but not for me.
And a word of advice -- if a company has dozens of advertisements for dozens of positions, each with a slightly differently-worded description or job title, they are probably a multi-level marketing thing.
Oh, also, they'll probably keep you waiting for an obnoxiously long time past your interview window. This isn't necessarily a dealbreaker for the second-round shadowing interview (which for me lasted from 9:30am to 8:30pm, yikes), but when you're only there for a five minute screening interview it can be a bit frustrating to sit in the lobby for 20-30 minutes, especially when the CEO keeps stressing in your meeting how important punctuality is to the company.
