Why is the 8bitdo SN30 so different from the SNES modkit?

I always assumed the mod kit for super Nintendo would be exactly the same as the fully assembled super Nintendo like controller at least in terms of features. The only difference they'd have to make is the slight shape of certain parts but all the chips and other components on the PCB could be exactly the same. The manual seams to suggest that they do not have the same features as each other.