It's the same reason it's a good idea to insist that people treat each other with respect when working together. The same reason you wouldn't decide to only hire people from your own family if you really wanted the best person for the job.
Any organization for-profit or non-profit that is run by people who care about meeting their goals and being good at meeting those goals would get this.
But sometimes organizations are more like gangs. All of this talk of excellence is a joke to them.