They think their paid security will keep them safe when the SHTF. Quaint.
Shades of feudal Europe: Their lords and peasants (or on this case paid mercenaries) will guard, defend and do their bidding so long as their fortifications, food stocks and armories hold up. Once there's a hiccup in any one of them, game over. With extreme prejudice.
Peasants are fickle like that.
When people find out what they did, the raw materials for thermite will be laid on top of their bunkers, ignited and they will melt away along with their bunkers.