I don't believe that. The purpose of a company is to make money for its owners. Dividends are payments to the owners of the money the company makes.
As far as capital gains goes, that is just a side-effect (albeit, a potentially lucrative one).
Put another way: Company X's stock is $100/share. They issue a 50 cent dividend. The stock price will go down to $99.50/share upon announcement. The investors/owners still have $100 whether the dividend is issued or not, except the investors have to pay taxes on that 50 cent dividend now instead of having it re-invested.
This traditional view holds that companies are fundamentally different than barrels of oil, in that they can produce wealth and provide reasonable returns to their share-holders year after year and that you can take your 7% appreciation at the rate the economy grows (or at least used to).
Timing the market is certainly a valid (if highly risky) strategy, but it's only one view of investing. It's only in this strategy which dividends don't make sense.
That statement is patently incorrect, in theory and in practice.
PRACTICE
The share price of companies that announce dividends every quarter has little immediate correlation to the dividend announced. In the long term, companies that consistently raise dividends year over year actually increase in value. (These are affectionately referenced as "dividend darlings" and are a focus of some investment strategies.)
THEORY
The purpose of a company is to make money. You do this by spending capital to create a product. Once you sell that product, you regain back the capital you invested in earnings. The goal is to eventually make back more money in earnings than what you invested in capital.
If I buy a bar in my neighborhood for, say, $100k, I would expect to make money back on it. If I worked hard to build a clientele and earned something like $30k a year from my customers (a spectacular return, by the way), then the bar would be earning money. I could then afford to pay some of that out to the shareholders - in this case, just me.
What your notion of dividends seems to be is a cannibalization of the equity present in the company. If the company has no product of intrinsic value, then yes, your example might hold true. In the bar example, you would believe that the bar is worth only $100k (the price I paid) and that any money I pay out would be coming out of that $100k. This would be true only if I did not work to get customers and therefore did not make any money over the year.
SUMMARY
For companies that provide value in the form of goods and services, the money you get out of it will be more than the money you put in. This frequently, and oftentimes should, take the form of dividend payments.
ALTERNATIVE
Having said all that, there are very legitimate reasons why tech companies do not pay out dividends, namely that they reinvest the profits in research and development to produce new and better products. I don't think anyone who bought Apple stock seven years ago is complaining about the lack.
Now that most companies refuse to wind down except in severe distress (you'll only get a sliver of the assets' market value) and don't pay dividends, the connection between profits and the investors is severed. The only reason share prices are vaguely correlated to profits is that investors are speculating on each others' faith in a mystical connection between profits and share prices. It's like a baseball card with the name of your favorite sales team on it.
The economy would function better if it rewarded buy-and-hold investors for good long-term governance of companies. Instead we tax dividends harder than selling out, make the share price all-important, and reward exponential over-expansion (that's largely where profits go, it's psychologically impressive even if it's less profitable) and market-timing speculators' games.