I used to smoke pipes. After I quit, I realized the back of every camera I had (along with my apartment, car, all my clothes...) smelled like pipe tobacco smoke. In time, the smell goes away. Like the desire to smoke.
I usually wipe down any camera that i get used with 99% isopropyl alcohol (maybe not to good for the leather) and then go over any leather with shoe polish. Usually that works pretty well. If not then I leave it outside for a while. That usually get rid of the smell for me.