It's important to note that traditional (shared) hosting or even a single dedicated server solution are not designed for scalable media hosting and delivery.
In terms of video storage for VOD, these alternatives provide no actual distributed redundancy, which means you could risk loosing your entire video library because of a failure in a single hard disk (or a local RAID, at best). Loosing a 200MB website is one problem, which you can eventually revert by re-uploading a backup in a matter of minutes, but loosing an entire video library of several GBs of content is a whole different issue.
In terms of content delivery (the actual process of sending the data from the storage to end-users through the Internet), these alternatives imply that all end-users connect to one single origin or host. When delivering a website, most individual files have a very small size, usually under 1MB each (images, CSS, JS...), which makes it possible for a single host to simultaneously serve a relatively large number of end-users. But when delivering video files, usually 10MB to several hundred MB each, and considering each end-user will most likely expect a sustained downlink throughput (from the single host to them) of at least 10Mbps, an evident bottleneck appears as soon as your audience grows to more than just a few users. That bottleneck translates into constant buffering or complete playback interruptions, which in turn leads to end-users abandoning your channel.
Furthermore, even the best cloud storage with distributed redundancy coupled with the best CDN (Content Delivery Network) might not be the most efficient way to manage your VOD content for a particular OTT platform such as Roku, because if no built-in method for updating the channel content is provided, you may need to perform this manually for each new video you upload or edit.
Frontlayer
http://www.frontlayer.com is a video platform that provides a service package specifically oriented toward Roku channels, including development, publishing, management and CDN integration. Besides counting on highly-scalable, geographically-redundant storage clusters and aggregating several Tier1 CDNs (i.e. Level3, Akamai), VOD content management is integrated with each corresponding Roku channel, allowing broadcasters to upload, edit or remove videos directly from a web-based interface, with no technical knowledge required.
For more information or also if you need assistance in evaluating different technical alternatives for hosting and managing your Roku channel content:
http://www.frontlayer.com/roku-channels--
Disclaimer: While I work for Frontlayer Technologies (not affiliated in any way with Roku), this post is intended to highlight the technical differences between different approaches for hosting videos, beyond Frontlayer's own commercial solution.