You raise a fair point wrt the context of the word, but this isn't actually a new use of the word "hack" or "hacking" or "hacker". In fact, if you read this link by our beloved rms:

http://stallman.org/articles/on-hacking.html

it would seem that the "old-school" (typically a more conservative) generation of hackers would not have found this use of the word "hack" incorrect at all.