For Chocolate : I made this library because I wanted to have other behaviors than those available in Vanilla or Extented, I think that design and ergonomics are really important and can change your approach (I'm not a specialist, but that seems obvious). Nevertheless, I understand that people prefer to use the native objects, my propositions are totally subjective and I think that a big part come from my experience with Max. Another reason of this work is that I have another project and I need some specific methods in the objects. I hope that you'll find this library more interesting when I'll be able to present this work.
For Coffee : I work with Pd Vanilla 0.45 so I don't really use extented and it was really fast and easy to code them so I did it... Except "prepend", I don't know where are this objects in Extented (I'll be glad to know it) and if we put the libraries in the extented distribution, we can remove my objects (it doesn't matter).
The names came from a stupid joke with a friend where Vanilla became Chocolate and Extented became Enhanced, nothing is really serious (don't worry, I do not claim to replace Vanilla or Extended). When I realized that perhaps others than me could be interested to use the library, I wanted to change the name to avoid mistake but it's really boring to do.