You’re completely missing the point. Their right to free association is in petitioning the government together. If a whole town agrees to stay off the public transportation grid as part of their choice to freely associate only with themselves, that may be a little odd, but within their purview.
To selectively only allow in public transport from whiter and more affluent areas, but not poor, black, high-crime areas is somewhat different. It is a form of ‘redlining’, and something that we socially, if not legally, don’t approve of—at least to the level of public expression.
Even still, that’s not the same as Sterling’s antebellum desire for his paramour not to be seen publicly with black men. It shouldn’t surprise anyone that a majority black league of players, its other owners, and its sponsors doesn’t want to be associated with such an owner.
The NBA owners did not "petition the government together". They simply acted in their own interests, based upon their evaluation of possible blowback from sponsors.
To selectively only allow in public transport from whiter and more affluent areas, but not poor, black, high-crime areas is somewhat different. It is a form of ‘redlining’, and something that we socially, if not legally, don’t approve of—at least to the level of public expression.
So only certain forms of "free association" are acceptable to you. Only forms that are "socially acceptable". And my point is, what happens if the standards of "social acceptability" change, to the point where redlining becomes something that the majority is no longer bothered by? Will you accept the new standard of social acceptability?