Final answer:
The act of tying up workers and stealing from a convenience store with the use of force or threat is categorized as a robbery, which is a violent crime.
Step-by-step explanation:
The scenario you described, in which armed individuals tie up convenience store workers and lock them in a back room, before stealing money, lottery tickets, cigarettes, and liquor, is an example of robbery. Robbery is a type of violent crime that involves taking someone's property by force or threat of force. It differs from burglary, which involves unlawful entry with the intent to commit a crime inside, and theft or larceny, which is simply taking something without permission but typically without the use of force or threat.