I am so sorry you had such a bad day! I realize it is such a lengthy written post because you are venting... which you need to do over something like this.
You pointed out the discrepancy you perceived in their advertising. The clerk responded unprofessionally. Whether the clerk was right or not in regards to the advertising, is a moot point. You chose to request a refund based on the volatile exchange.
The refund is either allowed or it isn't. If it is, clerk keeps the cigarettes, you keep the $. If it isn't, clerk keeps the money, you keep the cigarettes.
Not clerk keeps cigarettes and your $10. At the point where he kept your money without returning your cigarettes or vice versa, he actually STOLE your $10. So, this isn't just a customer service matter. It technically could be a law enforcement matter.
There are a variety of ways in which the situation could have been handled, i.e., seeing the manager the next day, contacting the owner, reporting to BBB and/or Chamber of Commerce, spreading the word about bad business, etc... but calling the police is also an option because he literally STOLE $10. If you had stolen $10 worth of merchandise from the store, he could/would certainly call the police.
So whether or not the police found this to be a minor and/or irritating incident, it is still HIS JOB to respond. And, incidentally, St. Charles isn't exactly overrun with crime, so it's not as though you are pulling him away from a daily stream of armed robberies, carjackings, and homicides. He could have responded more professionally.
Hope the remainder of your day goes better!