Geeeeeeeez..
Um.. here's a simple test. Find a friend who smokes. Have your suit jacket, have him blow smoke into it (be fair and dont blow THROUGH the material)with your nose on the other side. Then tell me your opinion. Some "may" not get rid of the entire smokey smell, but it is signficantly reduced if not totally unnoticeable.
Granted, I'm not dimwitted enough to totally think that every smell over the entire surface will be caught by a scent lok suit, and I surely can't tell what a deer can smell or not smell, but ANY small amount helps eh? Cost and "waste of money" is dependant on how the individual deems that.