"Thanks, and I put some free condoms in there, too!" Silva chirps.
In this technology-savvy north Alabama city, visitors won't just find burgers and prescriptions at the drive-thru window.
A "romance" store called Pleasures offers a rare convenience: a drive-through with adult novelties for sale. Business is brisk so far, with cars sometimes lining up three deep for vibrators, lubricants, lingerie and other risque items.
"It's been doing well, and really well on nights when it's cold or rainy," said employee Toni Kennedy. "Discretion and the ease of it are big, and convenience. We're Americans. We like everything convenient."
Even sex toys, as much as elected officials in Alabama have tried to prevent them from being sold in the conservative, Bible Belt state.
Pleasures is owned by Florida businesswoman Sherri Williams, who fought the state for almost a decade over what's considered by free-speech advocates to be one of the nation's toughest anti-obscenity laws. Among other things, the 1998 law banned the sale of products intended for sexual stimulation.
With two sex-toy stores in Alabama's Tennessee Valley, Williams sued to overturn the law with the help of the American Civil Liberties Union. She won initially when a federal judge ruled in 1999 there was no rational basis for the law. But the state appealed and Williams lost, allowing the law to remain on the books even though it wasn't enforced during the litigation.
The U.S. Supreme Court refused to hear the case in 2007, ending Williams' challenge. Distribution of sex toys is a misdemeanor on the first offense with a maximum penalty of a $10,000 fine and one year in jail, although the law doesn't ban possession.
But the law has a loophole that allows for the sale of sex toys that are needed for unspecified "medical, scientific, educational, legislative, judicial, or law enforcement" purposes, and Williams jumped through it. Customers buying toys - items that can be used for sexual stimulation - fill out an anonymous form with 10 questions including whether they or a partner have difficulty with sexual fulfillment.
In November, she held the grand opening for an expanded Pleasures store in an old bank building at a busy intersection. Williams first opened in the Tennessee Valley in 1993; this is her second expansion, and she has a smaller store in nearby Decatur.
It seemed like a waste not to use the old drive-thru window once run by bank tellers, so Silva and her co-workers now sell all sorts of adult products from the side of the building. Just like at a fast-food restaurant, there's a brightly lit sign outside with products and prices - herbal "enhancement pills" are $8 per dose. Williams believes her drive-thru is the first in the nation to offer adult novelties for sale.
The woman in one car wanted a rubber toy that spins and pulses. A couple in another vehicle stopped by for free condoms, which are advertised on a sign visible from University Drive, a main drag through town.
A few yards away from Pleasures, on the other side of a curb, workers at a neighboring McDonald's restaurant dish out fries and burgers.
Williams runs what she calls an "upscale" adult store, and using an old bank building with a brick exterior and manicured shrubs outside doesn't hurt the image.
"It actually has two vaults," Williams said. "It has a full-blown vault upstairs, and the basement is poured concrete with a vault door. This was a 7,200-square-foot bank."
Huntsville is a high-tech government and military town, and Pleasures workers say their customers include soldiers and couples based at the Army's Redstone Arsenal and workers from NASA's Marshall Space Flight Center.
On a busy Thursday night, the clientele looks like the crowd at the mall down the street young and old, singles and couples.
Inside, the shop has bright lights and royal-purple walls. The mood is mostly light, with friends giggling as they browse shelves full of rubber and plastic playthings.
But there's a more serious side to the business, too.
"People come in and say, 'I need something to save my marriage.' I've had that a million times," said Samantha Todd, who has worked at Pleasure for 2½ years. "I've had people come in and cry. It can be very serious."
The store includes an "intimacy clinic" that opens next month and will offer sexual counseling to couples and groups, but there are no how-to classes; all the assistance is verbal. It also sells instructional videos, books and a few magazines.
Employees check the ID of everyone who enters the store customers must be at least 18.
Police say they've had no complaints over Pleasures and don't pay it more attention than other stores.
"Right now there's not really anything for us to do with it," said Mark Roberts, a spokesman with the Huntsville Police Department.
The head of a New York-based nonprofit group that campaigns for tougher anti-obscenity statutes wishes government officials would work harder to stamp out businesses like Pleasures, and sex toys.
"I liken it to a cancer, a slow-moving cancer ... and law enforcement is ignoring it," said Robert W. Peters Jr., president of Morality in Media Inc. "It's been a battle going back to the 1960s."
Williams said her store and drive-thru serve a need for couples and individuals who need a little extra spice or excitement in their sex lives.
"Also," she said, "the police have already said they have a million other things to do."