DRIGGS BOY HAS CAKE, EATS IT TOO DRIGGS-Local citizens were shocked Monday to find that 10-year-old Jim Ferry not only possessed his cake, but was eating it as well.    Mary Giles was the first to discover young Jim, who ate as he sat on his front porch.    "It was the most atrocious thing I've ever seen," she declared, "who would think that such a thing would happen in our quiet neighborhood."    Mary's husband was hard-put to console his wife. "She's not going to get over this for some time. I don't think any of us will. I mean, what were his parents thinking?"    According to police reports, Ferry accosted the cake at a local Albertsons, where bakery employee Les Perry sold a slice to him for $2.49.    "I never would have dreamed the kid planned on eating it." he stated, "I just thought he was some local bearded kid that wanted his very own piece of cake or something."    According to his mother, the cake incident is only the latest in a series of bizarre occurrences at the Ferry household.    "Well, he has been wearing this fake beard for a week now. He got it in the mail. I just figured it was something he'd ordered from L.L.Bean, but ever since he got it he's been acting arrogant and self-righteous," she said.    Jim's father concurs. "I concur," he said.    "All I know is we'd better nip this little bugger in the proverbial bud," says Mary Giles, "Cos you know if we don't than before we know it we'll have professional sports and legalized prostitution in this town, you watch."