Yeah, sure, millennials might spend their money on frivolous things every now and then. But the fact that millennials like to eat something besides bread and peanut butter every now and then is not the reason why millennials can't afford to buy a home.
The real reason is homes are expensive AF and no amount of avocado toasts will change that. The New York Times breaks it down:
The truth is, even if millennials assumed the eating-out habits of baby boomers, it would take around 113 years before they could afford a down payment on a home (assuming a 20 percent down payment on the median price for a home in the United States, $315,000 in March 2017, and a 1 percent yearly yield rate).
Truthfully, some of us are spending a stupid amount of money on avocados, avocado toast, and things in general. Things are more expensive now than they were a generation ago. But let's be real, you didn't need that ticket to Coachella or that extra fancy brunch last weekend.