Of course they would. They are a taxi service, not a Dropbox or YouTube. They do neither have obscene demand for storage, nor for bandwidth, they need some serv

Of course they would. They are a taxi service, not a Dropbox or YouTube. They do neither have obscene demand for storage, nor for bandwidth, they need some servers tracking their users coordinates, running a "who is nearest" search in case someone wants a ride, some GPS navigation/pathfinding during the ride and some billing code after it. If you don't blow this up to stupid proportions, that should be able to run on modern hardware in a few racks at a colo for millions of users per day, especially since you can neatly shard the load geographically, thus distributing load (and rented racks) over multiple DCs, ideally with failover in place for emergencies. The only thing they really need to merge is the billing data at the end, but handling billing data of a global userbase of tens or hundreds of millions of users in a single system is a solved problem nowadays and does not even constitute a case worthy of the overused "big data" moniker.