Bashblog is a great tool but there we stuff missing in my opinion. So made a small fork (drop-in-replacement), with a few more features like menu, html5-compat, github-banner, etc. nothing fancy and based on my wants and needs alone.
Frameworks are useful to standardize how many developers in a single project develop together. It also eases binding dynamic views to datasources (databases or API:s or similar). And as a third i'd say that many of the everyday "gotchas" are sorted out in mature frameworks so the developers can focus on the stuff that actually matters.
I am - on the other hand - one of those who argue that frameworks also bring a lot of evil into development. Especially in JS where frameworks are built on top of frameworks which are built on top of frameworks. But I wont bring out those arguments here since the question was "Why to use frameworks" not "Why to avoid them".
Happy Hacking!