That's getting into territory where you could get sued civilly for the damages done to their car.

Fart spray and glitter are temporary and relatively harmless. Permanent dye in someone's home are car is just being a jerk.

so is stealing a package off someones porch

I certainly don't deny that.

Personally, I'm still not going to perma-dye someone's car.

We sure wouldn't want to upset people stealing our belongings.

One other issue is: they're criminals, they know where they got the package from and now they're pissed.

I won't deny the criminality. I'm still not going to cause them thousands of dollars in damage over it.

Use UV active dye (usually transparent otherwise) so they get shiny. Say, a package gets wet itself.