COLORADO SPRINGS, Colo.—An annual Easter egg hunt attended by hundreds of children has been canceled because of misbehavior last year. Not by the kids, but by the grown-ups.

Too many parents determined to see their children get an egg jumped a rope marking the boundaries of the children-only hunt at Bancroft Park last year. The hunt was over in seconds, to the consternation of eggless tots and the rules-abiding parents.

Organizers say the hunt in Old Colorado City has gotten too big for the hundreds of children and parents now attending. They canceled this year.

Last April’s egg hunt, sponsored by the Old Colorado City Association, experienced a few technical difficulties, said Mazie Baalman, owner of Rocky Mountain Chocolate Factory and sponsor of the event.

There was no place to hide the plastic eggs, which were filled with donated candy or coupons redeemable at nearby businesses. So thousands of eggs were put in plain view on the grass. A bullhorn to start the event malfunctioned, so Baalman, master of ceremonies, used a public address system that was hard to hear.

“So everybody thinks you said ‘Go,’ and everybody goes, and it’s over in seconds,” Baalman said. “If one parent gets in there, other parents say, ‘If one can get in, we all can get in,’ and everybody goes.”

Parenting observers cite the cancellation as a prime example of so-called “helicopter parents”—those who hover over their children and are involved in every aspect of their children’s lives—to ensure that they don’t fail, even at an Easter egg hunt.

“They couldn’t resist getting over the rope to help their kids,” said Ron Alsop, a former Wall Street Journal reporter and author of “The Trophy Kids Grow Up,” which examines the “millennial children” generation.

“That’s the perfect metaphor for millennial children. They (parents) can’t stay out of their children’s lives. They don’t give their children enough chances to learn from hard knocks, mistakes.”

Alsop and others say the parenting phenomenon began in earnest when baby boomers who decorated their cars with “Baby on Board” signs in the 1980s began having children. It has prompted at least two New York companies to establish “take your parent to work day” for new recruits as parents remain involved even after their children become adults.

Lenny Watkins, who lives a block away from Bancroft Park, took his friend’s son, then 4, to the hunt in 2009. “I just remember having a wonderful time, him with his Easter basket,” Watkins said, adding he can understand why a parent would step in.

“You have all these eggs just lying around, and parents helping out. You better believe I’m going to help my kid get one of those eggs. I promised my kid an Easter egg hunt, and I’d want to give him an even edge.”

Jennifer Rexford, who used to live near the park, said she participated in public Easter egg hunts with her boys, ages 3, 8 and 14. She doesn’t anymore, because of “pushy parents” that she said she has dealt with at the hunts.

“It just seems to be the mindset. People just want the best for their kids,” Rexford said.

Alsop said that dynamic is at play with parents who hover over their children, even into adulthood.

“I don’t see any sign of it abating,” he said. “It seems everything is more and more and more competitive, fast paced, and I think parents are going to see they need to do more to help their kids get an edge.”