I can't speak for other programs--I like C4D, but it's also what we use at work, so it's the one I know. If you're on a PC you may have more choices--Reiss Studios has plugins for a couple apps, including C4D. 

If by "crowd scenes" you mean "dozens" of characters moving with AI, I don't think C4D has that capability. You could have lots of low-poly figures running around, but you'd have to animate them yourself. The kind of software that does AI crowds, like MASSIVE, is like $50k or something like that.