I tend to agree with the last post. 3D shooting started as a way to practice for hunting situations...and it should have stayed that way...in my opinion.

To answer your initial question....I think that there are ideal characteristics for each type of bow on paper...but there is nothing that says you can't use a bow that would be more ideally suited for 3D for hunting instead.

In my mind, a 3D bow has to be relatively longer in axle to axle length to create the most stable shooting platform possible. Though a 3D's bow brace height shouldn't be extremely short and thus very critical to shoot it can still be lower than a typical hunting bow because on the 3D range you are under somewhat controlled conditions....which allow you to concentrate more on form, etc....

A 3D bow can be heavier in overall mass weight..again, to provide a more stable shooting platform. The heavier mass weight soaks up nervous "twitches" better. Though this might be beneficial in a hunting situation as well it is then at a cost to ease of carrying to and from your stand as well as when tracking the deer.

A 3D bow is generally set up more for speed and less for the noise/vibration level of the bow or the ability to shoot broadheads accurately and/or with attention to KE/Momentum issues.

Hope I didn't ramble too much.