I haven't seen the original document from Credit Suisse but from how it was quoted in Newteevee it seems that there is a strong emphasis on the heavy bandwidth

I haven't seen the original document from Credit Suisse but from how it was quoted in Newteevee it seems that there is a strong emphasis on the heavy bandwidth costs. First of all the ~30Tbps value is ridiculously large. Even then the report just assumes Google pays $1/mbit, which is the cost of cheap transit. However, Google only uses transit for certain indexing routes. Google peers very heavily at pretty much every major internet exchange. It's reasonable to assume they're using 10GigE and GiGE ports for public and private peering. (This is direct, usually payment free interconnection between ISPs; though there are services like PacketExchange which are a sort of hybrid between peering and transit). So on a per megabit basis they're probably paying 5-10 cents or so per megabit, maybe less though Google does have the cost of maintaining its backbone.