We have simple rules so that for any media type there is only a single possible encoding method that everyone agrees upon. This means clients can know exactly any type of content they come across was encoded. If there are media types that don't fit the normal pattern of naming, they may end up using an illogical encoding method.
I don't necessarily support this arrangement, but it's definitely far superior to what we had before where the publisher could choose any method which made decoding at the client tremendously complicated.
Graham
