Somehow, you always knew that the bland, sybaritic Spuds MacKenzie was really a suburbanite.

The beer company that has launched its bull terrier mascot into the marketing stratosphere tells an elaborate fiction about the beast: That it is male. That it is constantly surrounded by fetching women. That it is a jet-setter that lives in condos. And that it is ''The ayatollah party-ola,'' as a grown man who works for the beer company actually said.

Really. The dog known as Spuds MacKenzie is registered with the American Kennel Club as Honey Tree Evil Eye, but is called ''Evie'' for short. Reportedly she was born five years ago in Woodstock at the Honey Tree Kennels of Peggy and Richard Selk and then sold to Stan and Jackie Oles of west suburban North Riverside.

She is now pregnant, and lives in a two-story brick house on a quiet, middle-class street with a nuclear family-mom, dad, son and daughter. The famous dog is not outside much, according to neighbors, but Thursday evening when a reporter came by unannounced, Jackie Oles, wearing a Spuds MacKenzie sweatshirt, was sitting on her front stoop next to her famous pet, which was having an audience with several neighborhood children.

''I don`t talk to reporters,'' said Oles, who then scooped up the 47-pound dog, walked into her house and slammed the door.

''The family has tried to be really low profile,'' said Illinois Sen. Judy Baar Topinka (R., Riverside), whose proposed Senate resolution in Springfield honoring her district as the home district of Spuds MacKenzie was withdrawn after objections from Anheuser-Busch of St. Louis, the dog`s employer.

The cult of personality around the homely dog has grown hugely in recent months, and merchandisers report that she is now more popular on posters and T-shirts than ALF and Max Headroom. But fame has its price: Just this week, People magazine, in an article debunking the Spuds-is-dead rumors, tore aside the veil of mystery and published the full home address of the Oles family.

''We were very surprised,'' said Bill Stolberg, who manages Spuds MacKenzie`s image for Anheuser-Busch. ''But he`s become so popular that it was probably inevitable.''

''When they were telling the truth about the dog, they let me spend the better part of a morning with her and the Oleses,'' said John McGuire, a feature writer for the St. Louis Post-Dispatch. ''Jackie said that she is unusually calm and catlike for a bull terrier. She kept feeding her Raisin Chex out of a Ziploc bag.''

But Honey Tree Evil Eye, under her nom de chien ''Spuds MacKenzie,''

somewhat unexpectedly hit the big time, following Wheaton`s own cat-food-promoting feline Morris the Cat into the limelight. Her first national TV spot aired during last year`s Super Bowl, and the rest is history, as written on hats, mugs, calendars, jackets and other hot-selling paraphernalia.

''The family doesn`t talk too much,'' said a North Riverside neighbor of Stan and Jackie Oles who asked that her name not be used. ''Limousines come by for the dog, and they bring it out in a cage. But it doesn`t do anything spectacular. It just sits there.''

''They used to have a big statue of the dog in the yard,'' said village resident Barbara Andler, whose mother lives down the street from Spuds. ''They just took it down. I understand someone broke the ears off.''

''We`ve had no contact with the family,'' said North Riverside Village Manager Wayne Pesek. ''But we`re pleased to be sharing the limelight. Obviously it`s a better association for the town than some of the gangster stories in our past.''

Also pleased with Spudsmania is the local Ft. Dearborn Bull Terrier Club, which played matchmaker in getting Honey Tree Evil Eye together with the ad agency that came up with the Spuds MacKenzie concept.

''It`s always nice to have the general public be aware of bull terriers,'' said club member Mary Jung. The breed has suffered in the past because some people think it is a fighting pit bull, which Jung said it definitely is not.

But among those who frown on the poker-faced pooch is Scott Murphy, principal of Kenneth Murphy Jr. High in unincorporated Beach Park near Waukegan. At the start of this school year, Murphy officially banned Spuds T- shirts and any other garments that promote the use of alcohol.

''A few of the kids groaned at first, but we`ve had no problem with it at all,'' Murphy said. ''As a matter of fact, some parents have come in to say thank you.''

Meanwhile, in the fantasyland of marketing, Anheuser-Busch still clings to the crumbling Spuds mythology.

''He`s not a dog,'' said Bill Stolberg. ''He is an executive. He is the senior party consultant for Bud Light. Jackie Oles is just a member of his staff.

''He is the guru of good times,'' said Stolberg, waxing colorful. ''The granddaddy of get down. The grand pooh-bah of party-ometry.

''Once you start digging into his private life, it takes the fun out of it.''

But not for us, sir. We throb with pride to know that Spuds is one of ours.