There have been plenty of trends in the last decade-plus that have experts and internet trolls alike shaming the way people—especially millennials—spend their money.

Whether it's $5 lattes or over-the-top weddings, social media has made it easier than ever to see what people all across the world are buying and, if you're so inclined, to pass judgment on it.

The Stanley Quencher is one of the latest examples.

Fans of the tumbler have flocked to Target and other retailers to scoop up limited-edition colors and brand collaborations. Meanwhile, others wondered what the hype was all about and whether the $45 vessels were a worthy investment—especially if you're starting a collection. 

But self-made millionaire Tori Dunlap isn't so quickly joining the chorus of Stanley detractors.

"If you love that Stanley cup and you can afford it, great. Buy it in every color," Dunlap says. "If you want the Stanley cup, it might mean that you can't have this other thing, but that means that you should really want the Stanley cup."

Not only is your money yours to decide how to spend, but Dunlap also highlights the fact that a $45 purchase—much less a $5 or $15 purchase—probably isn't going to make or break your big financial goals, such as buying a house or saving for retirement.

"I hate the conversation every single time something new comes around where it's like, 'this is the reason millennials or Gen Z are financially struggling,'" she says. "No, it's not the Stanley cup, the latte, the avocado toast, the handbag, the manicure. That's not the reason you're financially struggling. It's a whole bunch of things outside of your control."

She highlights that the U.S. has more than $1 trillion in collective student debt, a lack of paid family leave, persistent gender and racial wage gaps and so forth.

"Those are a lot bigger deals when it comes to your money than, 'Did you buy a latte?'" Dunlap says.

Depriving yourself won't really help you achieve true financial wellness. But you do need to maintain a balance to ensure your bills and necessities are covered and you're saving for emergencies and the future.

"If you are sacrificing your future [financial] health to spend money on things that are really trendy right now that [in] a month or six months, you're not even going to remember you purchased or not even use anymore, let's make a different choice there," Dunlap says.

One way to help decide if a purchase is really worth it to you is to consider its cost per use, she says. "If you really love your Stanley cup and you use it every day, that cost per use is really, really low."

Consider a disposable water bottle you may otherwise buy. Even if it only cost $1, that's a dollar you could have "saved" by refilling your Stanley with tap water. It has a relatively high start-up cost, but every time you refill it, your cost per use goes down. If you regularly use it, you'll eventually recoup that cost.

"It might be $45 for a water bottle, but if you use it every day and you know that it's going to last you for years and years and years, that's probably actually a really smart purchase," she says.

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