Not getting into the politics of it or stating any illegal activity as per forum rules, this is about the flamethrowers themselves. Who would get one?
The two companies are http://throwflame.com and http://ion-productions.com/
Throwflame sells them for $1599 and can shoot 50 feet, while Ion Productions Team is selling them for $900 and they have a range of 25 feet.
Check your state laws first of course. They are useful for clearing unwanted brushes for farmers, one example of use. They can be shipped by USPS (just without the gasoline as per USPS rules against shipping flammable liquids).