So... as it happens I have a lot of experience deploying Meteor apps to servers that don't belong to Meteor. In fact, I may have a greater
variety of such experience than anyone.
As the lead developer of Sandstorm.io, I have deployed Meteor:
* As the Sandstorm front-end, where Sandstorm is designed to be installed by end users on their own machines.
* As apps that run on Sandstorm, and are designed to be extremely fine-grained (each app instance handling a tiny amount of data, e.g. a single document).
* As oasis.sandstorm.io, a highly-scalable centralized Sandstorm host.
* As apps.sandstorm.io, a fairly mundane use case (whereas Sandstorm is, comparatively, highly unusual).
I would argue that Meteor is not at all designed for Meteor hosting. Rather, Meteor is designed such that anyone wanting to build a PaaS around it will have a much easier time doing so than they will with just about any other environment. On Sandstorm, we find Meteor apps much easier to package than anything else, because the Meteor tools will output a self-contained app bundle that operates in a consistent fashion for all apps -- thus allowing us to write a common packaging tool that works with all Meteor apps. Other stacks are comparatively much more fiddly.
I would expect Meteor's hosting will turn out to be the best way to run Meteor apps primarily because they have kick-ass engineers there who will build an awesome product (disclosure: I know several of them), not because they've biased the framework in their favor.