The big business of survival bunkers

This has been going on for some time, it's an important issue but the OP is nowhere near the important parts.

One of those "better to sell shovels during a gold rush" type businesses?

"Traditional medicine" trade in critically-endangered animals and Western "wellness" supplements are also big trades. There's big money in lying to people who believe in magical thinking.

No one is ever going to be "saved" by a doomsday prepper bunker because it's entirely too expensive and unrealistic to maintain enough air filtration, water, food, medicine, and power generation/energy storage for even a single person to live sealed away for the rest of what would be their ordinary "natural" life. Preppers really therefore should be thinking self-sufficient farming/homesteading and essential medicines and supplies for common condition and acute injuries... but billionaires want TV dinner, safe room palaces so their selfish choices won't ever affect them in their minds.

Pay walled.