CNBC's Jim Cramer has found that millennials both hate and love change.
They hate physical change, so much so that they'd rather pay for a $4.32 purchase with a credit card than have to keep 68 cents jingling in their pockets or wallets.
But they love other kinds of change, the kinds that make companies more efficient, more "green" and more cost-effective.
"I've spent a huge amount of time on this show trying to figure out how millennials tick because they hold the key to growth for so many industries," the "Mad Money" host said. "You can't run a consumer business without appealing to the younger generation, and I tire of all the so-called experts who find kids these days to be unfathomable. In truth, they're anything but."
Cramer also found that the few things millennials are willing to pay premiums for help define their generation's spending activity.
First are ride-hailing services like Uber, perhaps because younger age groups can't afford cars or don't see them as a necessity.
Second are smartphones, particularly Apple's iPhone, which most generations, but particularly millennials, use for everything from work to communication to entertainment.
Third are cosmetics. As smartphones' camera quality improves, younger folks are turning to higher quality makeup products like Estee Lauder's to look picture-perfect.
But there's also a darker underbelly to their spending. As millennials increasingly move out of their parents' houses to become new homeowners, their wallets get stretched between paying off student loans, paying rent and paying for health care.
At the same time, their "green" streak is only blossoming. Cramer pointed to Conagra Brands' moves of reinventing old brands like Healthy Choice, putting out foods with fewer artificial ingredients and replacing plastic packaging with compost paper to make its products more appealing to millennials.
"Being in the frozen food aisle" has also given companies an unexpected advantage with younger generations, Cramer said.
Convenience, lower prices and the ability to stay at home draw millennials to frozen foods, so long as they have "clean labels," like International Flavors & Fragrances CEO Andreas Fibig told Cramer on Monday.
"If you can cut out the preservatives by flash freezing this stuff and keep the costs down, the freezer aisle can be a real profit generator," the "Mad Money" host said.
And while Conagra's no cruise line operator, many of which are getting boosts from bookings by millennials looking for Instagram-ready vacations, Cramer said it will still benefit from keeping pace with the changing landscape.
"Conagra understands and embraces the change that millennials are demanding. That's how you stay fresh. That's how you win, because my cohort? We think we're important ... but we're no longer clued in," Cramer said. "People my age are actually fine with antibiotics ... in our chickens and plastic? Oh, what the heck. It's fine. Millennials aren't fine with it. And like it or not, they're the future. I feel like my generation's become an irrelevant vestige of a branded past."
"Forget what you want," the "Mad Money" host concluded. "You need to know what the younger generation wants if you're going to pick winners in this stock market."
Disclosure: Cramer's charitable trust owns shares of Apple.