Here's why I buy $5 lattes even though everyone says not to

The author and her coffee
CNBC Make It

Friday, September 29, is National Coffee Day, meaning there are a handful of chains offering free or steeply discounted java to its customers. I'll take advantage of the freebies today, but you can bet I'll also have at least one latte this weekend, even though I've been told over and over: "Skip the expensive coffee and you'll be rich."

We've all heard that advice at some point. It's even the thesis of "The Latte Factor" by self-made millionaire and financial adviser David Bach.

The basic idea is that if you ditch your $4 or $5 latte every morning — or any small luxury you indulge in on a regular basis — you'd have quite a bit of money to contribute towards savings instead. Over the course of a few decades, that money could grow substantially, thanks to compound interest.

I happen to have a weakness for almond milk lattes, and while I don't buy one every morning, I still shell out $5 at least three times a week.

I'm fortunate enough to not have student loans and put about 30 percent of my income towards various investments each month. Coffee is an expense I've made room for in my budget and can afford.

Still, that's $60-$80 a month that I could be putting to work and letting accumulate over time. Trust me, I know.

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But it's an expense I can justify, and here's why. I don't just swipe my credit card and head out the door, drink in hand. I order to stay. Then I pop a squat and spend at least an hour reading, writing in my journal or setting goals.

I use the time to educate myself, to think of ways I can improve in various aspects of my life. And it's good for me: Successful people emphasize the importance of investing in yourself, whether that means reading consistently, taking a course or exercising.

Do I have to be at a coffee shop to educate myself? Technically, no. And I work on my goals in other ways too, like while training for marathons. But the coffee shop is a productive, distraction-free place for me. It serves as a designated time when I can focus on what I want to focus on.

For that reason, I'm going to keep ordering the $5 latte to stay, no matter how many compound interest charts you show me. And it's going to feel worth it.

This is an updated version of a story previously published in November 2016.

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