Are they? I'll be upfront in saying I've never done any actual work with parser combinators (I played with Parsec for about 15 minutes on the train), but I don't see how having direct control is worse. Easier, it may be, but I can only imagine real world situations harder when you get to the nasty stuff in your implementation (e.g. C++ templates basically need to be "run" while being parsed, or lexed even)