Thee is a certain logic there, but it's not reall the logic that drives stock prices. While it's true that the "backing" of a stock is a claim on the assets of the company in the event of dissolution, from which one could infer that distributing assets reduces the value of stock, the reality is that stock purchases are not based on valuation of the company—despite the fact that he whole idea of a market cap presumes they are—but on the expected value realized from the stock stock, which is driven by two things (1) expected payouts while holding the stock, i.e., dividends, and (2) expectations that someone else will be willing to pay more in the future for the stock (largely driven by perception that future growth or potential buyouts are not fully priced into the current market price.)

Establishing a practice of paying dividends feeds into #1 to increase the perceived value of holding the stock.