Comment by Keyframe

Your question also hides an answer. You don't often get to chose a group of people you work with, and unlike projects that self-attract and self-distill ideal profile (like linux mentioned in sister comment), you're left with people usually not used to ye olde C idioms. With C++ it's a bit easier since it is more widespread and supports some of the idioms people get used through schools and other projects. Of course, projects (should) always dictate a certain discipline by different mechanisms, but if certain way of thinking isn't ingrained then it introduces just that much more pain to the communication layer between people.