For me, two points:
(dating myself here) Minimum wage used to be $5.75 when I was in high school. I worked my ass off for an entire summer. I fuckin hated it, but we all gotta hustle. Around my last shift, I came out to the parking lot, and someone had done my car dirty with a hit'n'run. No note, no CCTV, nothing. The damage was in the neighborhood of $2k, which is exactly everything I had saved up that summer.
I worked my ass off 300 hours to break even. It might as well just have been some community service work release program. Fuck capitalism.
The other is when I was older, post-grad. I had a shitty job where I had to pony up for own health insurance plan with high deductibles. I started having random tingling in my joints, so I did the responsible thing and had it checked out. I got sent to several specialists who ran a battery of tests. I'm already in the hole, $3k out of pocket, and all I got was, "We're not sure what's wrong."
The tingling lingered, and I started looking up information for myself on alternative, holistic sites. Someone had listed similar symptoms and said it was just a vitamin deficiency. That couldn't be it, right? Well I ordered some supplements, and within a month, the tingling was gone.
$3k down the hole. Fuck capitalism.
The 2008-2009 recession. I watched my parents nearly lose everything as the floor fell out from under their feet. Spent the remainder of my teens working to help them and later support them in my early 20s. Several years of adulthood wasted trying to make sure they could survive.
When Obamacare passed, it hit me again when I was forced to buy insurance and looking over everything I was offered and suddenly realized it was a scam. The entire thing was a bail out for insurance companies. I could barely afford one plan and none of them covered dental. I will never forget going home, pulling up the actual bill online and reading it. I sat there for an hour thinking to myself; how the fuck is this supposed to help me or ANYONE who is poor? Only people being helped are insurance companies.
I had a friend growing up who was able to travel the world with a church ministry. One thing he told me after we reached adulthood and it stuck with me in my mind. He traveled all over the world and said that he kept asking himself growing up; how come I see poor people everywhere I go? He left the church and started reading Marx and Stalin and I feel blessed I had him as something of a mentor to guide me.