This may be the answer -- check out this ebay informational page:
https://ebaypartnernetwork.com/files/hub/en-US/qcp.html

It looks like ebay is paying external sources for "quality clicks" that result in ebay sales and/or generate paypal fees.

I'm a novice at this, but it appears that it's possible to generate revenues, in excess of site fees, etc. by being an intermediary between chip or silver strike collectors and ebay ... depending on the volume and success of referrals. Not limited to the chip & token world either -- could be done for coins, stamps, hot wheels, barbie dolls, any collecting or other area with a following and an available website name.

With the right developer tools, it's probably near 100% automated in doing searches, updates, deletes, etc. once it's set up.