App Store and iTunes purchases: You can't delete history

We don’t typically run one-word answers to reader questions, but it’s worth it in this case, because we regularly receive a question similar to this one from Macworld reader JLR:
I want to dump, forever, some music and iPhone apps from my iTunes account and not have to deal with them just “hiding.” Is this possible to do?
No.OK, I can’t help myself, I need to give a complete answer here. Apple lets you hide purchases from appearing where they typically display in a