HockeyRef please see it from this side. If there is a "web" version, YOU can run it from your webserver and db server within your practice. You still own the application and your data.
However, for those people who prefer zero footprint, AC can offer an HOSTED version.
This is the best of all possible worlds: platform independence, hosted or un-hosted.
The non-web EHR's I have seen try to "host" a windows app thru citrix.
