LOS ANGELES (Reuters) - For a recent TV commercial, H&R Block's advertising agency passed on using actors and instead chose Riley Holmes, who works at the tax preparer's Chicago office, to pitch the company's free "second look service" that claims it can find new deductions from prior returns.

"People bring in old tax returns and I'm like, 'Who did this to you?'" says Holmes in the 30-second TV commercial.

With hit reality shows luring viewers to just about every channel, H&R Block is among a growing number of companies, including Bayer, Best Buy Co Inc and Ford Motor Co, which are jumping on the trend and casting their own "real housewives" and other folks who don't act for a living in spots.

Advertisers' growing use of "real" folks in commercials is among a growing list of challenges facing actors as the union representing 165,000 actors and media professionals, begins bargaining on Thursday on a new three-year-contract. Industry negotiators are expected to resist efforts to raise actors' rates for the increasing number of commercials that appear online.

"People want the real cancer survivor, the real doctor, real fire eater," said Carol Lynn Sher, who works for the CESD Talent Agency in Los Angeles. "Fewer actors being used for those roles and its taking away jobs."

Many already chafe as they watch a growing number of A-List actors - Robin Williams in a Snickers bar commercial or Sofia Vergara for Pepsi - take jobs that used to go to them.

"My 13-year-old daughter Francesca has been auditioning for commercials for five years, and it's harder than ever because now they want kids to be real ballerinas, real violinists or real gymnasts," said Toni Farina, mother of a Los Angeles-based young actress.

The issue of real life people taking actors jobs isn't likely to be formally addressed in the Screen Actors Guild (SAG) and American Federation of Television and Radio Artists (AFTRA) advertising negotiations.

Those talks, the first since the two guilds merged, will be focused mostly on higher pay for ads shown online and larger contributions to the union's health and pension funds.

SAG-AFTRA declined to comment on the negotiations.

Still, the trickle of real folks in commercials has intensified, since actors signed their last contract in 2009.

In better days, actors used to get as much as $50,000 in residuals for a commercial that played nationally for a year, said Mike Abrams, partner with AKA Talent Agency in Los Angeles.

The appeal - not to mention price tag - of some actors are driving ad agencies elsewhere, especially as reality stars like Bethenny Frankel from "The Real Housewives of New York City" or "Jersey Shore" star Nicole Elizabeth "Snooki" Polizzi start showing up on magazine covers and hawking products.

Walt Disney Co's ESPN went even one step further and searched for real "dead" people for a campaign last summer of 15 to 30 second commercials titled, "It's Not Crazy, It's Sports" featuring real-life stories about fans who took their love of their sports teams with them to the grave.

"We did a nationwide search of funeral parlors for sports fan stories and how people took their love of their teams to the grave with them," said Dan Bell, a Los Angeles casting director who specializes in real people casting.

Chuck Kaczorowski, chairman of Kaczorowski Funeral Home in Dundalk, Maryland, was among the stars in the ad campaign, in which he talks about a Baltimore Orioles casket his funeral home offers.

Many companies now even want "real life" couples and families to make their ads authentic, said Bell. The downside is that sometimes they clam up. Other times, they catch the acting bug, and start performing for the cameras.

Bell said he also helped find a real mother and her special needs child for a Mass Mutual ad that aired last summer as part of its campaign to drive awareness of challenges facing families with children with special needs.

As negotiators for actors and advertisers gather around the table for talks, LA actors likely have their attentions divided.

"I don't think anyone's worried about a strike at this point, but they are worried about this trend to more reality commercials," said Sher, the talent agent from CESD, which is a major talent agency for young television and commercial actors.