If you click Get Data in the bottom left, and then directly to "Get" under "Services", or from "Get" under "My Organisation" and then switch from "Organisation" to "Apps" ... then either way you get a long list of third party providers to Power BI Apps.
However, if you go to "Apps" (third item down in the main menu on the left), then click the "Get Apps" button top right, you see your organisations apps fine, but clicking "Apps" from here brings you an empty list. Am i missing something and missunderstanding the intended difference between the two or is this just broke?
@AndyA The Apps in your list on the main page is for organizational only. It is weird that it shows you the same pop up without the other external Apps...(Content Packs). My guess is that we are in a transition period between Content Packs and Apps. That eventually, you will have external Apps that you could use in your Org Apps space. Or maybe paid apps that would show there.
Can't say it's a bug persay, but the other Apps you can grab externally still download a dataset/reports/dashboards directly to your workspace. So they behave differently.