If I recall correctly Google built its own network gear long time ago. Completely makes sense. Looking at Cisco product with regard to security & the recent NSA leaks you really don't want your network gear from them.
The big difference here is that states can simply buy access to, e.g., a Cisco Nexus and attack it from inside and out until they find a vulnerability in NX-OS, let's say, a malformed CLI-via-HTTP call.
Whereas, what software does a Google switch even run? What's the architecture, the APIs? You basically need someone inside Google, or for one of these things to fall off a truck. Way more involved and expensive than the 10k you might spend on a Nexus to throw it your lab and set your hackers on it.
Actually, Google has published papers and have presented talks (many of which are available on Youtube) on the type of gear they have developed. I don't know what their latest versions are, but recently they were using OpenFlow style infrastructure to provided fine-grained control (security, balancing, analysis) over flows through out their network. OpenFlow style constructs also provide a micro-segmentation style control (ie distributed firewall) over ingress/egress of traffic at the individual container/vm port level.
Ah shareholder value. Value is the keyword. It's not shareholder money per se. If a companies stock jumps because people think you are bold for making your own secure network equipment then you have created value. Security and privacy can make value. Look at Apple. Public perception of Apple makes up a nice part of their stock and it's based around (just to name some smaller ones) privacy and security.
Well mostly because they don't rely on any legacy code base but they can write it all by themselves. Also Google has somewhat of an reputation for security other than Cisco.
Think of it in the same terms as any other service you're contemplating: do you want to pay other people for proprietary stuff, or do you want to pay your own people to develop skills around open stuff?
cisco has an incentive to not look foolish, but they don't particularly care about any small or mid-size accounts. Your people have an incentive to care about your security and functionality. Weigh up the advantages and disadvantages and make your choice appropriately.
That's the sort of thing I'm talking about. Good implementations of known-good crypto.
I don't doubt that Google's trying to come up with new, novel cryptographic methods as well, but those take a long time to develop, test, and get reviewed. RSA didn't show up over-night and SHA3 has taken some time to get ready for production.