If gun sellers lost their license to sell guns for 3 years following these kinds of thefts, just watch how fast they install safes, hire armed guards, or do other things to prevent such thefts.  Right now, no skin off their backs.  Their insurance companies just reimburse them for their losses.  And the general public and law enforcement pay the price when these stolen weapons are used.  After all, nobody is going to this trouble just so they can shoot holes in paper targets with Hillary's or Obama's face on them.