This is just dumb. Nobody says that marketing is not marketing if it benefits the business, or HR is not 'pure' HR if its priorities align with the company's strategic objectives. CSR is about managing changing expectations by society on the business - it is not philanthropy.
On that basis, the whole suggestion that CEOs are giving away investors' money is no more meaningful than to say that, given that we know that only half of our company's advertising works (although we don't know which half) means that the marketing director is irresponsibly giving investors money away.
Whether they like it or not investors rely on the senior management to manage the business - the whole of the business. They aim to see the real value of the business increase, and the long term value of the shares to reflect this. Those shareholders are owners - but they have never sought to micromanage the business on other aspects. Generally they understand that the management of the business are closer to the realities of the business than they are, and they should be allowed to manage and measured on the results. You don't like it, you don't have to own the shares.
Note, the speculators do not count here. If you temporarily own shares and treat them like gambling chips then you are not an owner, particularly when there are devices you may use to make money when the value of a business goes down, not up. Gamble well, but we do not care what...