NEW YORK (CNN/Money) - When the treasures of King Tut toured the United States in the 1970s, Steve Martin wrote an homage to the "Boy King" that included the lines:

"Now if I'd known the line would form to see him/ I'd take up all my money and buy me a museum."

That would be an even better deal today. No matter how lucrative the first Tut show was, the projected revenues for a new, improved 2005 exhibition tour will dwarf them.

The Egyptian head of antiquities told the New York Times he expects the exhibition to generate at least $10 million in each of four (or more) tour cities next summer. To accomplish that, the museums will charge admission prices of up to $30 a head.

Back in 1978, the suggested donation to visit New York's Metropolitan Museum of Art was just $2, and the museum did not charge anything extra to see Tut.

It's not just dead pharaohs that are causing prices to soar. Museums across the country are extracting stiffer tariffs from the paying public.

The Museum of Modern Art (MOMA), following a $858 million renovation of its Manhattan galleries, began charging visitors $20. MoMA's uptown rival, the Guggenheim, charges $18.

The Met, which still seeks donations only, will up its suggested donation to $15 in January. The modest-sized Frick Collection, extracts $12 from attendees to view its Rembrandts, El Grecos, and other Old Masters.

Outside Gotham, the situation is little better. Boston Fine Arts charges $15. In Chicago, the Art Institute charges $12. The L.A. County Museum gets $9 and the Philadelphia Museum of Art $10.

There are some notable exceptions: The massively endowed Getty, in Los Angeles, is free. So is the National Gallery in Washington and all of the D.C. Smithsonian venues.

In general, though, the cost of culture is ballooning almost everywhere, raising the question: why?

"The price to operate a place like MoMA is $50 to $60 per-person," says Anne Butterfield, a Massachusetts-based independent museum consultant. "Admission prices seldom pay more than 40 percent of the cost of operation."

Most pay much less. According to Edward Able, president of the American Association of Museums, entrance fees account for only about 5 percent to 10 percent of the average museum budget. The bulk comes from memberships, donations, government grants, and endowment proceeds.

"Admissions don't begin to touch the actual cost of operating a museum," he says.

Moreover, costs have soared in recent years, a trend Butterfield traces to several factors:

• Government support has dropped about 30 percent over the last 10 years. Governments want to encourage museums to run on a more business-like basis; they will no longer blindly subsidize deficits. Even state or city-owned museums are ceding control to private, not-for-profit groups.
• Endowments have not kept up with expenses. Some museums suffered investment setbacks when the stock market tanked, says Able. Even if they haven't actually lost money, they haven't gained as much as anticipated.
• Standards of care have gotten more stringent. Curatorial work and storage, preservation, and handling of art works has been upgraded, which can cost more than merely warehousing items.
• Visitor care costs have also increased. Governmental requirements tied to safety regulations and entitlements such as the Americans with Disabilities Act have pushed costs higher.

Many museums are housed in older buildings with ornate facades, antique plumbing and heating, and outmoded environmental facilities.

"The real issue," says Able, "is the expense of maintaining these huge, aging facilities."

Museums exist to serve the public, according to Able and most other experts in the museum world. It would seem that, at least potentially, high prices could conflict with that mission by discouraging attendence.

But Able points out that 98 percent of all U.S. museums that charge admission also offer reduced fees to various classes of visitors. Seniors, children, and students all qualify for discounts, and school groups are often admitted free. Also, he says, 70 percent of these institutions have free visiting days at least once a week.

During the decade of the 1990s, when many museums raised prices and other, once free institutions began asking for donations, attendence soared. There were 486 million separate museum visits in 1989, according to Able, and 850 million in 1999.

With attendance nearly doubling in 10 years, it seem that lovers of high culture are willing to pay to follow their passions.