I've been a PHP developer for many years now, with many tools under my belt; tools that I've either developed myself, or free-to-use solutions that I have learned to trust.
I looked into CodeIgniter recently, and discovered that they have many classes and helper routines to aid with development, yet saw nothing in the examples that I couldn't do just as easily with my own tools. Simple things like DB abstractions, Email helpers, etc. There was some interesting code relating to routes - mapping urls to the right controllers; but even that's not particularly difficult to code yourself if you've ever written an MVC style web app with pretty urls.
Even after looking through some of the other popular frameworks, I still see nothing that would be that much of a time-saver. Even looking at the forums, I see people struggling to get the tools to work for them. I do understand how they would be more useful for junior developers, since full system design skills take a while to understand and appreciate fully.
Yet, I'm often told that I should use an off-the-shelf framework to produce my solutions, but I still remain unconvinced. What's the real benefit to someone like myself? Am I just being elitist, or is this a common opinion?
Edit: Looking at some of the answers here, should I perhaps consider packaging up my toolset as its very own framework, writing some documentation and posting tutorials? If I'm hesitant to take on other's frameworks, would opening it up and getting more eyes on it help to improve my own skills/tools?