Walmart is going to build the largest hosting company in the world?
Companies plan for utilities to go out, which don't even have competition. It's insane to operate just hoping Amazon doesn't get hacked, freeze your account, experience a catastrophic failure, or just decide to quadruple the price overnight.
If uptime has any relevance to your company at all, have (and test!) a process to move everything to another provider in a mostly automated fashion.