This is an excellent question,
I had put a wrong link in my blog after the heading “Requirement 3”, which was supposed to be “ https://github.com/testcontainers/testcontainers-scala”. Yes! It’s fantastic way of getting your docker up and running as part fo the functional tests. In fact, i tried that before I went on to this pattern.

The main difference here is, your environment is not your spec. Environment is build and spec is tagged to the build. Spinning up an environment should be easy, without running tests. But that’s not the only reason.

The philosophies and the technical issues of a different pattern is atleast vaguely explained in many part of the blog, especially in the sentences under the Requirement3. Since this is a very nice question to ask, I have gone ahead and edited the blog to point out more reasons and issues (which i will uncover in much more detail in my next blog). Thanks a lot for your patience.