If the smarter, more forward-looking CEOs were convinced to come aboard, the others would tend to follow. That sounds cheap, shoddy. That sounds like communism. It's much more effective to sell the concept on the basis of reliability, instead. Big corporations lose millions of dollars per hour when their datacenters go down.
Executives are keenly interested in avoiding that.
Also, even concerning their desktop boxes, executives are aware of the money drain. As an installation ages, that shrinks to less than a day. With Linux, a box left alone has MTBF of around two years. An executive who allows his company to becomes dependent on software he is not allowed to see inside, let alone change, has lost control of his business, and is on the wrong side of a monopoly relationship with a vendor who can thereby control his business. With open source, the executive is in control, and nobody can take that away.