Private property owners, yes, but this was a business, a resort doing business with the public. In case you hadn't heard, the public now includes black people. Private property rights are a poor refuge for public racism.
It has nothing to do with racism, as I would have no problem with a black property owner restricting access to whites, or whoever else he (as the owner) wants to restrict.
Was it? The guy who locked up the pool was head of the home owners' association. Tells me that the pool was associated with a private home development. They have rules and are free to restrict how many guests can access the pool, etc.
If the pool belonged to a resort, then there's no way this guy could be 'head of the homeowner's association.'
There's something screwy with this story.