The thing is that petty crime affects the man and woman on the street and it infects lots of others too who figure out, whelp, I guess this is how it works/ A politician embezzling is bad but you don't experience it directly --but for your tax dollars not doing what they are supposed to be doing.

People can put up with a sleazy politician but they can't live comfortably knowing they can't trust their neighbors or trust the police to fight crime for them when the police know DAs will reduce charges, drop charges, etc. Like why bother putting in hard work where you're putting your wellbeing in the balance just so that criminals go unpunished... eventually you end up with a "Caracas" & wild-west experience.

We don't punish politicians who run scams, and the result is predictable.

These two things don't rule out each other.

Quite to the contrary, when we observe rampant cheating from the presidency down to shrinkflating food and freeriding the subway, it is a good argument for having an universal morality problem.

There isn't a dichotomy between the saintly people and the scummy political class. A nontrivial part of the voter base of the scummy politicians is formed by regular scummy voters.