Can you think in which condition you want ready made objects from container?
Its not container's job.
Yeah container can handle your Db connection and datasource.
Mostly we want some basic plain text data from container to initialize application.
You can make/use your own application to fullfill your requirment..
Like dependency injection in Spring framework.
If any other has difference thinking can put his/her point..
Perhaps, an object about container itself? I know, we can get this information through methods. But, just for an example. My idea is - let's do in terms of objects. IMO, database connection and data source perfectly match such requirement.
I've never been into big/complex enterprise applications. So, I am sure I'm missing many scenarios where we could implement this idea.