Why should a majority be able to decide who and who doesn't get to participate in the market?
If you don't think this is legitimate, two questions:
1. Is it legitimate for the government to restrict foreign participation in markets, or to place rules like tariffs on their participation?
2. Was it inappropriate for the greater military force in the US in the 1860s to decide that Southern plantation owners could not participate in the cotton market if they continued to use slave labor?