The difference is that the loopholes rich people use generally actually exist, while the "loopholes" advertised by sovereign citizens are obvious nonsense like "by filing the right paperwork I can make the government give me a million dollars they're keeping in a secret bank account for a government-created corporation that's named after me except with all caps".

Trickle down economics is disproven. Trickle down corruption is real.

They don't find them, they pay to have them created.