This surely create some negative opinion about bitcoin if it gets used on such tobacco and other form of alcohol based stuffs it'll surely be under controversy that bitcoin is purely for drugs and other illegal activities. This should not happen, by the same time decathlon managing to add bitcoin payment by 2020 is truly a big thing to happen.
I see what you mean, Ayiranorea! A lot of people are biased and only think in the box. It is a common thing in human psychology to associate the things in front of them. So if they see they can pay with BTC only/mostly in the tobacco shops they might associate it with the "dark side" of our society. However I think it is a risk worth taking if it brings more awareness and actual use for Bitcoin. Personally I am thinking of ways of how to implement Bitcoin in my city in a more smarter way, but the fact that there is no legal framework for cryptocurrencies yet gives me a lot of hurdles to find solutions for...