In the past there had been unpleasantness on the steps of the state Marriage Licence Bureau, Joni says, with chapels literally fighting it out for couples' attention. Her efforts have helped bring about an uneasy truce.
"A lot of people, they won't even be in the same room with each other. I am the common denominator."
About 100,000 couples a year tie the knot in Sin City. That is down from a pre-recession high of 120,000 but still big business and doesn't include vow renewals and commitment ceremonies (the Nevada version of a civil union). At $60, marriage licences alone are a good earner for the state.
First stop on our mini tour is Vegas Weddings, a stone chapel with stained-glass windows sitting incongruously on a busy modern street. Its proximity to the Marriage Licence Bureau means it gets seven to 10 "walk ups" a day (ie people who decide they must get hitched then and there and literally walk up to a forecourt window). Those after a drive-thru ceremony can use the "Fast Lane".
Vegas Weddings does plenty of traditionals as well, in its chapel or on a terrace overlooking the street. Both venues are fitted with webcams. Doves and balloons can be released from the terrace.
Like many of the chapels it is a complete service with on-site wedding planners, photographers, florists, and a small reception room. All up, a simple ceremony and cake reception will cost about US$1100 ($1580), an economical option for couples wishing to avoid the drama and expense of a huge family do, Joni says.
Next we visit one of the biggest outfits in town, Chapel of the Flowers, with 63 staff including eight in-house photographers. It is like a series of little movie sets - three chapels, a gazebo, Romanesque terrace and a garden made of glass flowers. Staff member Wendy says: "We can do anything and everything that a bride wants."
It has featured on Happily Ever Faster, a reality TV show about the Vegas wedding business. It's good publicity, Wendy says.
She agrees with Joni that the industry must work towards removing the "stigma" Las Vegas weddings still carry - tacky Elvis chapels and drunken late-night exchanges of vows a la Britney Spears. The Britney incident had the phones ringing off the hook, but the headlines "kind of set us a little bit back," Wendy says. "You can have an elegant Vegas wedding you can be proud of."
Having said that, the stop I am most looking forward to is Viva Las Vegas - a themed wedding chapel in a converted motel.
Unlike the other two venues, gay-run Viva Las Vegas will do commitment ceremonies. It will also do pretty much anything you can dream up.
Its chapel (I use the term loosely) is kitted out with professional theatre lighting, a high wire and large double doors for the purposes of driving a pink Cadillac in as required.
It has a props room and a costume department. Employees come from an entertainment-industry background because they understand what's required in transforming the chapel from an intergalactic theme to a beach party to an Egyptian scene at 30-minute intervals.
"We have the best Elvises," staff member Victoria, a former dancer, boasts.
For Elvis ceremonies, one of the motel rooms has been turned into a 1950s diner, complete with neon signs, jukebox and Formica tables.
The venue's busiest day is Hallowe'en - last year it did 78 ceremonies, three at a time from 9am to 11pm.
"There were a couple of traditionals, but everything was really graveyard, gothic, vampires," Victoria says.
Joni says number days such as the coming 10/10/10 are also big. So seriously do they take the business of marriage in Vegas that Mayor Oscar Goodman volunteered the occasion of his 47th wedding anniversary for a large promotional renewal of vows ceremony, held on Fremont St in the heart of "old" Las Vegas on 9/9/09.
I ask Joni how she retains her boundless enthusiasm in the face of the Elvis suits and the high divorce rate. She describes herself as being in tourism first and the wedding industry second. There is also satisfaction in seeing people's vision come to life.
And "I'm a true romantic at heart," she proffers. "Tiger Woods, I'm so mad at him."
CHECKLIST
Getting there: Air New Zealand in conjunction with partner airlines flies daily from Auckland to Las Vegas. Return economy fares start from $2317.
Getting married: Vegas Walk Up ceremony - US$79. Chapel of the Flowers, Garden or Gazebo ceremony - US$698 (includes bride's 18 rose bouquet; limousine service; two weeks online ceremony broadcast). Viva Las Vegas, Hound Dog Special - US$260 (includes Elvis singing one song and performing ceremony; stuffed Hound Dog keepsake; live internet coverage).
Further information: Contact LV Wedding Connection.
Maria Slade travelled to Las Vegas courtesy of Air New Zealand.