“Sin Taxes” are the fun name for Pigovian taxes that are designed to “disincentivise” certain behaviours. Although the way I like to think about it: they’re compensating society for the social cost.

For example: take smoking cigarettes. While smokers might like to declare that smoking is a victimless crime: in a nation that provides any form of public healthcare, the illnesses that are associated with cigarette smoking are going to mean that smokers will probably end up benefiting from free healthcare more than the rest of us*. In order to compensate for that extra usage, the government imposes a sin tax.
*And I know that we can come up with anecdotal examples of grandmothers that smoke a pack a day and live to the age of 95 – but it’s the public perception that’s at play here. 

Which is exactly why we should be imposing a sugar tax on snack food: not to disincentivise (we’ll all probably still snack), but to compensate for higher medical costs.

Anyway – here’s an infographic that you might find interesting. It’s a little self-righteous, but the statistics are fun.