Advertising has no value.
In this day and age the concept of "targeted" advertising is promoted as if it's the salvation of mankind. Or at least more viable than random sponsorship.
Back in the 1950s there were TV and radio shows which had only one sponsor. Magazines of the time were full of ads which were presented at a low price for the companies. Costs of producing media were not so high then as they are now.
The proliferation of choice for consumers of entertainment (such as 500 cable channels) means each production has less value to them. This lowers the quality of programs as the need to mass-produce entertainment to fill the gaping maw of consumer attention overwhelms, while at the same time increasing the over-all costs of production as fewer resources can be concentrated on any one project.
And so we have the dilemma of advertising costs having to increase, and the need to convince companies that their ads are a worthwhile expense in terms of return on investment. Thus the concept of "targeted" advertising, wherein the company is persuaded that their ad is more certain to reach an audience likely to respond to it.
In the old days this was accomplished by the quite simple method of categorization: people interested in golf would buy Golf Digest, so companies selling golfing equipment would advertise in that publication. More general audience appeal made evaluating the potential customer more difficult, and so ... "targeted" advertising was born: analysis of the consumer base of any particular venue to convince companies it was the right choice for promoting their product.
Now in the modern age of consumers being flooded with choice it is ever more difficult to convince a company that their ad will actually be seen by someone who might buy their product. This results in the over-analysis of the consumer base, and the inaccurate and useless "targeted" advertising we see today.
In short, if anyone buys your company's product it is more likely due to random chance than effective advertising strategy. You may as well give the money to charity, because in effect that's what you are doing; incurring the (admittedly tax-deductible) expense with very little chance of getting anything in return.
Today advertising is valueless.