"Just put as much of your income as you can spare in a market tracking fund and let it grow." Reliable and simple, going for that S&P pegged ETF? Congratulations, you just gave a loan to UnitedHealth, ExxonMobil, PhilipMorris, Amazon, Tesla, etc. Even worse, you've done so in a fashion that rewards the status quo. For every $5 you've loaned to some present day, world destroying juggernaut you've loaned maybe $0.50 to some company trying to cure cancer.
Common counter arguments:
1. "I'm just trying to get by, man."
Okay, it is absolutely a luxury to be able to invest at all.
2) "You're not going to beat the market. What about my retirement?"
I hear this from my friends and it is incredibly frustrating. Correct, you won't beat the market. What you're saying is you want to earn your fraction of a cent for every baby seal that gets clubbed for sport to maintain your gains, just like everyone else. Great. What a society. What are the gains you really need, and what are you willing to support for those gains?
3) "Sir, this is a casino."
I actually agree with this, but myself and I'm guessing a majority of people don't play it that way.
Voting with your dollar includes how you invest.