Theft as a legal matter rests on the foundation that when something is taken from another against their will, it is a thing they have legal title to. Because if that isn't the foundation a thief has as much complaint against the police who confiscate the property he has stolen. The law establishes what constitutes that title.
If you live here and pay taxes you are paying them willfully, participating in a system from which you derive benefits. Living in this compact is prima facie an agreement on your part to abide by the rules, to obey the law and to bear your portion of its freight. If you don't agree with the premise strongly enough you can remove yourself and are free to find another that suits you, leaving those taxes and participation behind.
A theft of small things is a tort, trespass to chattel, and often trespass to land.