Wasn't Amazon already doing this with their amazon lockers?
http://online.wsj.com/article/SB1000087239639044354550457756...
It's a pretty weak argument considering that Amazon has the infrastructure muscle out someone like Bufferbox, if there is no distinct competitive advantage for the startup.
And of course, the open platform to all carriers.
If that is the case, then Bufferbox is in a more defensible position.