How much of a state's revenue comes from optional taxes?

I’m thinking of things like vanity plates, cigarette/alcohol taxes, lottery tickets, hunting/fishing licenses. What percentage do they make up of a typical state’s income?

Depends on what you’re going to classify as “optional taxes”.

For example, you’ve included excise on tobacco and alcohol products, presumably on the basis that buying these is a choice. But surely buying any grocery item is a choice? You don’t have to buy, say, milk any more than you have to buy beer; you can eliminate either or both of these from your diet. So are all value-added taxes/sales taxes on grocery items “optional taxes”? If additional fees for vanity plates are an optional tax, what about standard fees for standard plates? Nobody is required to own a car. If the country levies stamp duty on real estate transactions, as many countries do, are they optional taxes? Nobody is required to buy real estate; you can rent a home. And so forth.

In many states, grocery items like milk are not taxed at all. I know they aren’t in Maine.

But lots of countries have general sales taxes/value-added taxes. And whether they apply to groceries or not is beside the point. Nearly all purchases are optional; there are very few things you are legally required to buy. Nearly every purchase you make could have been substituted with a different purchase, or replaced with a decision not to purchase, but to save. So, to the extent that you do purchase items which attract any kind of excise, sales tax, value-added tax or the like, do you class all those taxes as “optional taxes”? And, if not, why is excise on beer an optional tax?

And the same goes for a fee for a fishing licence. If that’s an optional tax, isn’t the fee for a driving licence also an optional tax? Both are licences which you get because you like to include those activities in your lifestyle, but in neither case are you obliged to include those activities in your lifestyle.

Here are the categories Missouri uses (pdf) and the latest numbers

Income tax = $7,463,060,672 or 48% of all revenues
State sales tax = $3,430,314,960 or 22%
Local sales and use taxes (the state collects and returns to local governments) = $3,134,151,262 or 20%

Everything else combined (including property taxes, estate taxes and revenues from gambling) works out to about $1.5 billion or roughly 10%

Also in optional is the income tax. You don’t have to work – or work as much or for as high pay as you choose to do so.