1. If you ban something you'll obviously sell less of it. That's the whole point. And banning a popular product will decrease the sale of other items, because it decreases the exposure people have to manipulative marketing present in convenience stores.

2. If you ban something you'll obviously increase crime statistics because people are now being charged for it. Doesn't mean they're doing it more. It may look like they're doing it more, but that's because people are paying attention now.

These are the same arguments drug dealers use against banning meth, cocaine, heroin, and all the other illegal drugs. In reality, if they where legalized people would use them more because there's less risk for the same reward. It doesn't matter that you can regulate it because 1. people will still sell it illegally and 2. people will now be using the 'safer' product more, thus scaling up to more harm than the 'dangerous' product did before.

It's like banning murder, and then complaining that there's less murder, but also that people are being arrested for murder.