Occasionally, one will here in the argument against open borders: “How many immigrants will you let into your house?” or “Why don’t you have any immigrants living in your house?” or some variation thereof. These retorts miss the point of freedom.
Freedom means the right to do something. The flip side of that is the right to not do it. Freedom of movement, for example, means I have the right to move from Virginia to North Carolina. It likewise means I have the right to not do so. Freedom to purchase tobacco necessarily means the freedom to not purchase tobacco. To call for the freedom of migration between countries does not imply any form of contract to house or employ immigrants. What it does do is call for the freedom to contract with those individuals for all people. I may not want to hire person X for a job, but that does not mean no one should hire person X.
In a free market, everyone is allowed to buy what they with with whomever is willing to sell it to them (barring violations of the rules of justice, of course). Likewise, a person is free to not buy anything.
Advocates who use the above argument (other variations include “people who support gun rights should be shot first” or “people who want abortions should be forced to listen to the heartbeat”) fail to understand the dual nature of freedom.