[jessaustin]

That may be true for simple home purchases, but I know some active real estate investors and they really value the services of buyer's agents. These guys don't buy something in the hopes that it will appreciate in future. They buy something only when they know they're stealing it. ("Victims" vary: could be an out-of-touch heir, an overextended builder, a bank that's held onto a repo for 11.5 months...) On the day of the closing, they've already made their money. The right buyer's agent knows the business, the locale, the seller, everything he needs to know. When asked, however, he doesn't know his employer's name. That's valuable.

[amatai]

Agreed, but that's not the market Zillow/Redfin are serving.

In fact, I think, the right term for those kind of agents is whole-sellers, who scout around for kind of deals you mention.