Freedom to travel means I can go anywhere I'm welcome and no one has a right to stop me. It doesn't me mean I can go into your house if you don't want me there. There are employers in the US that want to hire workers from other countries but the government prevents workers who want those jobs from traveling to where they are. This is a violation of the rights of the employers and the workers. The workers don't have a right to trespass on private property while they travel, but private roads, airports, and bus services will be happy to offer their services. If the owner of one road won't do business with Mexicans another will. If there is a need in a truly free market an entrepreneur will fill it. Government funded roads are subsidies for the automobile industry and in a free market we would have flying cars to take us where we want to go.