KMST 1.2.409 - Thief/Pirate Revamp

Cannon Shooters have stance and they're a ranged class.
Mechs have 100% stance from the beginning and they're a ranged class.( Well, in 4th mainly)
It seems like nexon wants all the pirates to have some form of stance, even if they're a ranged class..

I don't have an excuse for Cannon Shooters, however Mechanic was already explained a few posts up.

I dunno why CSes have it, but it's not justification for Corsairs getting it. If nothing else, you could always say that the huge cannon adds a bit of weight, making monsters unable to push you around. Corsairs, however, have small guns.

Even if you don't want to agree with that reasoning, "This class has it so that class should too" is never a reason.