The July issue of Vogue, the women's fashion magazine, features a willowy model in a drab-colored, raggedy, tattered dress tied as limply as a shabby robe, and another in big floppy shoes with rag-like ties around the instep and ankle. Their resemblance to the homeless shopping-bag ladies who sleep on hot air shafts in winter and on park benches and in doorways in summer is not incidental. It's fashion's latest: street couture, the bag-lady look--expensive designer clothes with rips, pins and rags manufactured right in.

In the best of times, the fashion industry's new fascination with the poor could be considered insensitive and in bad taste. But when the ranks of the homeless poor in our nation's cities are growing and our leaders are fattening the coffers of the rich at the expense of the poor, popularizing the bag-lady look seems cynical and downright perverse.

Cuts in government programs of welfare and food stamps, high unemployment and the release of mentally ill people by institutions have swelled the number of people who are homeless and on the streets. Official estimates put the figure at 2.5 to 3 million nationwide, the highest level since the Great Depression. The new homeless include factory workers, lumberjacks, teachers and social workers.

Just when the warm weather masks, rather than ends, the problem of the homeless, the fashion gurus step into the breach.

The look first surfaced at Bloomingdale's in New York City under the heading of "street couture." The street people who usually lack a voice in our society found one there in the person of the Rev. Joseph H. Gilmore who led a small demonstration of homeless people and their advocates outside the store.

"At Bloomie's, the rich can get dressed up just like the poor," Gilmore, who works with a Union Theological Seminary soup kitchen, told the press, adding that the high-priced clothing "mocks the poor." He might have added that the poor cannot get dressed up just like the rich--exactly the point.

Amy Haas of the New York Coalition for the Homeless added, "The condition of poverty and homelessness are cruel and brutal things not to be romanticized and stylized especially by those who are far removed from the situation. For people like us advocates, it's just unbelievable. This seems to be promoted as a harmless, carefree lifestyle. It's not. Fashions don't take into account the disease, the assaults, the ulcerated swollen legs. It's one thing to misunderstand the problem, but another to promote a romanticized version and overlook the facts."

These deliberately tattered- and stained-appearing clothes are not to be confused with the fad among teen-agers and dancers who rip off hems and sleeves in the interest of comfort. These clothes are popping up not only in New York but also in other places around the country.

And it isn't only in fashion that the misfortunes of the poor are callously being converted to cold hard cash.

In Nashville, two women have started a party business based on the people who wander through streets living off the bruised fruits and bread crusts and leftover yogurt that others throw into garbage cans. One of the women explained the origins of the bag-lady routine she does with a friend to liven up parties, special occasions and conventions.

"I started this bag-lady thing about four years ago to entertain my family," Mary Jane Forsythe once commented. She and her partner, Sybil Chance, will show up in a limousine if clients want them "real classy." They consider it a perfect blend of American craziness.

If mocking the poor is a perfect blend of American craziness, what can we expect next?

I thought I had seen it all when blue jeans, the unofficial uniform of the '60s flower children and students who marched and sat-in and registered voters, were affixed with a designer label and put on the streets of Paris and on Fifth Avenue in the '70s.

But yet another recent example of how fashion knows no shame in converting anything to money-making uses was the abortive attempt to cash in on the Gandhi revival. Someone actually tried to convert the homespun cotton that Gandhi wore as a political statement into an expensive, high-fashion look. That failed.

Peter Carlsen, writing in Gentleman's Quarterly about "Fashion's Breakdown," said, "Clothes no longer predict attitudes, but reaffirm them." If he's right, the attitudes exemplified by these riches-to-rags clothes say a lot about where we are right now in the '80s, and what they say is shameful.