Beyond keeping the images slim, the times I'd reach for awk when dealing with a docker container would be when I'm debugging problems within that container. I might need to do some quick text parsing or finagling in order to troubleshoot why the application is sucking.
I'd rather not need to upload a Java script into my docker container just for quick troubleshooting.
For anything beyond that, I would very greatly prefer to have "black box", extremely verbose log dumps and database dumps that I could analyse over at my actual dev machine, or a good debugger that lets me step through the code to figure out what's going wrong.
I do realise that not all languages have good tooling, or that some people prefer to use `printf` style debugging, so it may not apply to all.