I'm still using Bootstrap on my own small website for nearly this reason, and I still haven't really found a reason to install the framework to customize my build of it. My traffic is simply too small, and my site unimportant enough. The default options are just fine, and with minial effort look great on all the mobile devices I have at my desk to test with.

I don't use the CDN links though; something just doesn't sit right with me with that option. I'm glad it's there, and I'm sure it helps newer programmers or those that want to just toss it in a template to see how it works, but I'm not comfortable relying on a third-party server to house such a critical part of my site. I always self host those files in production.