Earlier quoted context omitted.
> Investors buying more shares with dividends doesn't decrease the number of shares outstanding. If you increase the share price without decreasing the share count, you have created value out of thin air and are saying the company was more valuable without the cash than it was with it. You're wrong. When the company issues the dividend, the share price falls for precisely the amount issued. So if everybody used that…
You're wrong. The market cap already had the cash priced into it, regardless of how it was used (as a dividend or re-invested). By your logic, a company whose profits remained flat and issued a dividend would become less valuable every year until it was worthless.
There is a value in a future dividend. On the ex-dividend date, the share becomes less valuable because the new holder will not receive a dividend in X days. This X is usually very small, so a share that goes from paying you $5 in two weeks to not paying you has clearly lost value close to $5.