A HERD of cows has just left the Arvanigian family's store. But the owners aren't a bit fazed by it. Underneath those fluttering plastic udders is just another group of partygoers outfitted this week at the popular Halloween Outlet in Worcester, Mass.
What the superstore owners find remarkable, however, is that not a single child is among them.
Adults are no longer just escorts standing in the shadows behind their trick-or-treating pirates, vampires, and witches. Increasingly each year, they are joining in the festivities with the same fervor as children.
From parties and parades to house decorating and dressing up to greet trick-or-treaters, adults are celebrating Halloween with expectations as large as Linus's in Charlie Brown's Great Pumpkin patch.
Americans will spend $2.5 billion on Halloween this year, according to the National Retail Federation (NRF) in Washington. About $850 million of that will be spent on candy alone.
And, according to Advertising Age magazine, companies will spend an estimated $157 million to promote the holiday.
''The amount of money spent reflects the enormous growth in the popularity of the day,'' says Jack Santino, professor of Folklore and Popular Culture at Bowling Green State University in Bowling Green, Ohio.
But adults don't seem to view Halloween as a commercial holiday, Mr. Santino says. ''There's the element of creativity that gives people a real sense of personal engagement.'' It's not a holiday sponsored by church or government - you don't get a day off - and anyone can join in. ''People make it happen.''
Many of the adults playing dress up today are trick-or-treaters of the 1950s and '60s, when Halloween was primarily a children's holiday, Santino explains.
''Baby boomers recognize the value in much of what they did as children and see no need to leave that.
''There's a difference between being childish and childlike,'' Santino continues. ''These people want to keep the innocence of childhood alive.''
Many baby boomers who have children of their own now take the ''fun'' aspect of Halloween seriously. ''When I was a child, you never saw adults in costume,'' Santino says. ''It's changed.''
According to national consumer research conducted by Hallmark Cards, 1 in 3 adults will dress up for Halloween in some way this year, up from 1 in 4 just a few years ago.
The No. 1 reason people cite for participating is ''to involve children,'' says Hallmark spokeswoman Linda Fewell.
Halloween Outlet customer Tom Crowley would agree. As he struggles to contain his restless young daughter in front of the Snow White and Mermaid costumes, he says: ''The kids act as a catalyst for adults. You try to do it up.'' He adds that he and his wife decorated their yard with signs, cats, and a stuffed scarecrow.
Barbara Bouchard, from Holland, Mass., is shepherding four children toward the cash register - past a group of teenagers trying on wigs and singing to the song ''Monster Mash.'' She's not dressing up this year, but she did decorate her house inside and out. ''People need something [to celebrate]; it's just too long between the Fourth of July and Thanksgiving,'' she says.
For many adults, with or without children, Halloween has also evolved into an opportunity to masquerade, not unlike Carnival or Mardi Gras. ''People look at Halloween as a fun-filled night or day to pretend to be someone or something they're not. It's really a release in today's society,'' Greg Arvanigian says.
Another reason Halloween is successful is that it is well-keyed to the fall harvest, observes Santino, who wrote the book, ''Halloween and Other Festivals of Death and Life'' (University of Tennessee Press). Think about the smell of a lit jack-o'-lantern or burning leaves, or the feel and sound of crisp leaves underfoot, he points out.
Halloween also helps promote a sense of community. ''It's an opportunity to know your neighbors better,'' says Marilynn Stobbs, a St. Louis resident whose house takes on a ''haunted'' look every Halloween with dry ice, fake bats, and other props.
''We've had a lot of little people move into the area,'' explains Mrs. Stobbs, whose seven children are all grown now. ''They bring their parents and visit with us. We enjoy it so much.''