They see Walmart as a store they pay at for groceries. And they see Bitcoin and Centralized Exchanges as a way to get rich.
You make it sound as if it's mostly the users' fault. Sure, there's definitely responsibility individually, but what would you expect if I was the CEO of the most popular exchange? What if I portrayed Bitcoin as a way to make a quick lolly and had excessively good traffic and advertising in social media and search engines?
That being said, add that governments constantly try to brainwash everyone. They say that it's a direct threat to the economy, but in reality, it's direct threat to their control. When was the time when Christine Lagarde stated that cryptos are not currencies? Didn't the commercial banks send to everyone that they should not use cryptos as they're financially risky investments? How many times has the cyber crime secretary scared everyone for the volatility?
Stop living by "their" rules. As I said, I have literally never had a problem with tainted coins because I will not use any service which enforces arbitrary rules on me.
This is not so simple. If a quarter of the total merchants accept Bitcoin using BitPay or Coinbase etc., you're unable to use many services. Same happens with Tor; you're excluded by many websites. Is that due to some government order, is it due to the fact that they feel they're fighting spam, whatever, you have this drawback.