[riams]

Losing a decent chunk of change? How can they lose something they wouldn't otherwise have had at all? It's only normal to assume that they have special terms for Starbucks, but it doesn't mean they're losing anything.

Unless you mean that Square is providing the service at a loss to Starbucks?

[jcdavis]

Yes, I would guess they are providing this service at a (slight) loss to Starbucks.