In short
The calling of Matthew took place on the main route from Syria to Egypt (known as The Way of the Sea), which also passed by Capernaum, as Matthew was sitting at the Capernaum toll station. Tolls, like the wealth tax (Matthew 22:17) were one of the taxes levied by the Romans.
On the main route from Syria to Egypt (known as The Way of the Sea), which also passed by Capernaum. All the goods entering the territory of Herod Antipas were taxed at the Capernaum toll station. In Roman times there were four kinds of general taxes that had to be paid, property tax, wealth tax (Matthew 22:17), tolls (at ports and city gates), and in Jerusalem also municipal taxes.1
9 As Jesus passed on from there, he saw a man called Matthew sitting at the tax booth, and he said to him, “Follow me.” And he rose and followed him.