I had this mindset for years. "It's not real programming. It's for people with no brain", I would tell myself. A lot of other developers share this idea, I think.
However, I currently am in the plan of launching a series of blogs, somewhat related to each other. I figured I'd try out wordpress, just to see what it's like, and also because I plan on having other people working on these blogs.
Whoah! Completely blown away by wordpress and how quickly I can set things up. PHP is quite simple, and the built-in functions are very helpful.
If you plan on just launching some products, learn wordpress. If you want to learn a programming language, go ahead and write the entirety of the code base yourself - that's the only reason I can think of to not use wordpress (for myself).