Let's turn it around. If you invest 120 dollars into your retirement fund every year for the next 40 years, you'll end up with 33.5k. Instead, you spent 4.8k. The person who listened to a few commercials is up 40k on you at retirement.

This is an extreme example (after all, you're not going to spend 10 dollars on Spotify for the rest of your life), but the principle of the matter stands: Money saved now will be worth more later thanks to compounding interest. In a sense, the dollars you earn today are the most valuable dollars you'll ever earn.

It's up to you to make the judgment call on a case by case basis whether you'd like to live in the moment, or whether you'd prefer to save. Everybody draws the line somewhere (I personally have a Spotify subscription), but to call it irrational is... a bit irrational.