You're just lucky. Most big cities do not have this tax. NYC tried it under Mayor Bloomberg and it failed miserably, and so Bloomberg took the idea to the West Coast where it's succeeded in some cities.
Stuff You Should Know did a podcast about it. Well, it was about Sin Taxes, but soda tax is a sin tax:
http://www.stuffyoushouldknow.com/podcasts/sin-taxes.htm
The great irony of sin taxes is that the majority of them usually aren't implemented to cut down on the sin, and those who pass the tax are trying to get rich off of poor health choices. It's one thing if the soda tax
directly goes into a fund to educate people to make healthy choices. I would not be against that very strongly, if as close to 100% of all raised funds from the sin tax went into education programs and alternative programs to cut down on that sin. But they don't. In most cases especially with light sins like Soda Taxes, 20% might go to that, and 80% will go into a general fund. In affect, the local government (or whoever is instituting this) is trying to get rich off of poor health choices without adequately informing the public about their poor choices.
Plus, the verdict is still out if all sin taxes actually work, especially when it comes to soda taxes or sugar taxes which are very rarely applied regionally and usually hyper-local.