Why a repo can't be part of multiple projects in bitbucket?

[Federico Vidueiro]

I have many projects with shared components that are in independent repositories, so I would love to have them "packaged" as part of all of the projects that make use of them.

[Johannes Kilian]

That would be difficult with the repository permissions. The repository can have it's own distinguished permissions - but it also inherits the permissions of the project it belongs to. What if one project is very restrictive with permissions and the other project very liberal? What policy should be inherited from the projects for the given repsoitory?

Bitbucket projects are not projects to organize repositories according their functional structure (as you would like to) - Bitbucket projects are meant to group repositories with the same superordinate permissions on the first hand.