Courts only care about cases that are brought before them. They're not out looking for cases, that's what law enforcement does and LE is going to look at the context. If the ambulance is being driven by a carjacker they will cite it for being in the park even if it caused no damage. If the ambulance is driven by a medic and responding to a call they will likely overlook it. And of course they'll drive their own cars in the park whenever they want.

If that is how US police works then I can assure you it kind of make sense why you have people hating them.

Thats some Animal Farm. Can someone that knows US law confirm this?

What I mean is that the exceptions should be written in the law and there should absolutely not be a case where you cherrypick.

I'm sure police everywhere have discretion (whether enshrined in law or not) over who to charge.

Where do you live that you think police exercise no discretion at all?

Prosecutors also have discretion in who to prosecute.

Courts also make decisions on guilt.

The police generally have immunity from prosecution (forms extremely dangerous outcomes) and are not obligated by law to do their jobs.

I can tell you we have rules that supersede for ambulance drivers and such.

We have had many cases where a thief have been caught by the store owner and the store owner is the one going to jail for entrapment.

Where? Again, I highly doubt that the police there don't ever exercise any discretion in at least some situations.

I have an anecdote contrary to this - When I was in the US, a friend explained to me how drug dealers tended to live in private trailer parks in part because it was harder for law enforcement to get into the general area without a warrant.

Basically, the rule of that park was "no (police) cars in the park" and the police could in fact not drive their own cars in the park whenever they want - only whenever a judge wants them to.

I think there's a degree of US specificity to your comment. The situation in the UK would be different.