I see this reason a lot. Thing is, Bootstrap was never designed for your use case. It was always a framework to get started, meant for developers to build their designs upon.

Think of Bootstrap as a model car kit. Bootstrap 2 was a Porsche that had just enough paint that people ran with it in their showcase, but that was never Bootstrap's intention. You were meant to complete the kit before showing off. Version 3 is a Tesla, but this time no paint.