ST. LOUIS -- Lyndsey Shaw has been on the front lines of Black Friday in years past, helping to open the Best Buy store in Brentwood, Mo., by 5 a.m.

But when Best Buy decided to follow other retailers this year in moving up its opening time to midnight on Thanksgiving, Shaw worried she would have to miss her family's tradition of going out to see Christmas lights after their holiday dinner.

"We don't usually get everything cleaned up and out the door until 10 p.m.," she said.

Fortunately, her supervisor allowed her to work a Friday afternoon shift instead.

But with several other retailers, including Macy's, Kohl's and Target, also opening at midnight for the first time, a groundswell of protest has been brewing among people who worry that not all retail employees will be as lucky and that some will have to skip out early on family gatherings.

And moreover, critics assert, the earlier opening times are encroaching too much on a holiday that should be reserved for family -- not for shopping.

The strong backlash in recent days has left retail trade groups a bit perplexed.

Ellen Davis, a vice president for the National Retail Federation, pointed out that other workers -- including movie theater and some restaurant employees -- already work that holiday.

"Their employees aren't up in arms about it," she said. "It's almost ironic that on Thanksgiving, people are complaining about having a job."

And if consumers don't like it, then they don't have to go shopping that day, she added.

Some retailers are taking it one step further. Toys R Us is opening at 9 p.m. Thanksgiving Day, an hour earlier than last year. And Walmart is rolling out its first round of doorbusters at 10 p.m. -- two hours earlier than last year.

So have retailers finally taken Black Friday creep too far?

Jane Charbonneau thinks so. The Creve Coeur, Mo., resident recently signed an online petition on Change.org that asks Target to push back its opening time to 5 a.m. The petition, which was started by Target employee Anthony Hardwick in Nebraska, has garnered more than 100,000 signatures.

"To me, it's just the principle," said Charbonneau. "We only have so many holidays in the year. I'm a very family-oriented person. I think it's only fair for the employees to have some time off for the holidays."

As it is, her family may have an earlier Thanksgiving meal than usual so her two children who work retail jobs can get to sleep and report to work around 4 a.m. on Black Friday, she added.

But in their defense, retailers say they are just trying to better serve shoppers who would prefer to shop at night rather than having to wake up in the pre-dawn hours on Black Friday.

"We have heard from our (customers) that they want to shop Target following their Thanksgiving celebrations rather than only having the option of getting up in the middle of the night," Molly Snyder, a Target spokeswoman, said in an email.

She added that Target does its best to work around the schedule requests of employees and offers holiday pay to all hourly workers on Thanksgiving.

Adrienne O'Hara, a Toys R Us spokeswoman, wrote in an email that the response to its 10 p.m. opening last year was "overwhelmingly positive."

In addition to allowing families to get a jump start on holiday shopping, it helps the store better manage crowds and traffic, she said.

Defenders also note that shopping often is a family-oriented activity so it doesn't necessarily clash with the spirit of the holiday. And the midnight sales are apparently more appealing to the younger generation.

Shoppers in the 18 to 34 demographic were twice as likely to shop at midnight on Thanksgiving last year as other age groups, said the NRF's Davis.

"It should come as no surprise that young adults want to stay up late rather than to wake up early," she said, adding that Kohl's, Target, Macy's and others opening at midnight "see the young adult crowd as the apple of their eye."

The 35-plus crowd, by contrast, is more likely to arrive at stores starting around 7 a.m. on Black Friday, she said.