In response to changing priorities, Steve Branton, a CFP who works with high-net-worth clients in San Francisco, said the safe portfolio withdrawal rate for retirees at his office now assumes that their assets will be fully depleted after 30 years.
"Only if the client wants to leave the principal to their heirs do we deduct a fraction of a percent of the safe withdrawal rate," he said.
John Gajkowski, a CFP with Money Mangers Financial Group, has observed a similar phenomenon, noting many baby boomers feel they've "done enough" for their kids. But there's a selfless motivation to keeping more of their hard-earned savings, too.
Read MoreStuck in sandwich generation
"Previous generations believed that the kids took care of the parents when they got older, but baby boomers don't believe that's the way it should be, and for themselves they want to be far more independent," he said. "They don't want to be a financial or physical burden to their kids."
As a result, boomers are highly motivated to stretch their limited dollars further, using tax-efficient withdrawal strategies and "leveraging up," using life insurance-based or asset-based annuities to cover future medical expenses rather than relying exclusively on traditional long-term-care insurance.