Subscribing to a taunt, item or any misc means there is a higher chance of it being added to the game, the more there are, the more noticable it will be for Valve. If the taunt is added, it can possibly be on the Mann Co. Store. You can not get it for free unless you helped created the taunt in which case you will get a Community/Self-made version of it.

Thanks! :)

No problem, happy to help.