Like Free-to-Play games and Casinos, they "make their real money" on whales. Go step foot in a Best-Buy; 95% of the time, the employee-to-customer-ratio is about 5-to-1, or worse.
To be clear, I think basing one's business on that concept is delusional at-best, but its what a "profitable" retail chain has looked-like to share-holders for at least the last 30 years.

I knew eBay fucked-up, but $55 billion? That's couch-change to a lot of businesses with much worse brand-recognition. At least their turn-key operation isn't over-valued by orders of magnitude...