First and foremost, there are about 71 million millennials in the United States. CreditCards.com surveyed 1,000 people. It's unclear how many of those thousand people were millennials -- but whatever the case, it's obviously a fractional representation of the overall population. It's like finding a hair in your ice cream sundae, and assuming every ice cream sundae ever must contain hair now (probably because of millennials).
Secondly, the data loosely classifies restaurants, and includes fast-casual, fast food, and take-out options.
And, being the youngest generation on record here, millennials are naturally going to be the generational segment making the less overall money. This is paramount. Not only would this factor into being less able to drop tips in general, but more importantly, it also ensures that the kind of restaurants millennials frequent, would probably be ones that you don't normally tip at. Sure, when I get a slice of pizza, I'll commonly toss a buck or two in the tip jar if I have it. But more often than not, I don't.
It specifically calls out (in a bullet point) that Millennials are most likely to select the "lowest" option when presented with multiple tipping options, "as you might find at a food truck or coffee shop or after taking an Uber," when traditionally, those options usually start at 18% - 20% -- generally accepted as the threshold for a "good" tip.
Finally, it does take into account the fact that 27% of millennials would prefer a system that does not rely on tipping to give servers a decent wage (meaning, "hey, let's start actually paying people who work in restaurants like they're actually human beings"). But it doesn't explain the why, and also uses it as some type of pseudo-excuse for our "poor behavior."
Let's get this straight: this may be my opinion, but I have a very hard time believing anyone that is committed to the no-tipping movement -- which, essentially, boils down to wanting to give service workers a more livable wage -- would take it out on the servers themselves by refusing to tip. Chalk it up to my faith in humanity. And my distrust of loose Internet studies that get picked up by major media outlets.
But if you are reading this, if you're a Millennial yourself, you know that we aren't inclined to tip less than our parents generation, or our grandparents generation. You also probably know the reports of us "killing" every industry that Americans hold dear have been greatly exaggerated.
And you (hopefully) know that every Internet-based study claiming so, should be taken with a grain of locally sourced, artisanal sea salt.
Luckily, we still haven't killed salt.