1. Speed bumps, stop signs, or red lights on the road between your house and a gun store.
2. Inclement weather on a day when you would like to go buy a gun.
3. The 2nd Amendment's mandate for a "well-regulated militia."
4. Gathering statistics about gun violence. (They literally argue this)
5. People choosing of their own free will not to have guns. (Seriously, read up on Mandatory Carry proposals)
6. Gun manufacturers, distributors, and buyers paying taxes.
7. Anyone spending money on anything other than a gun, because lower volume sales means higher prices = an impediment to purchase.
8. Peace and tranquillity, since lack of motivation to buy a gun is unconstitutional.
9. Saying or doing anything that in any way impedes, inconveniences, irritates, offends, or contradicts a gun industry executive, since this could negatively impact their work and hinder the Constitutionally guaranteed production and sale of firearms.
10. Failing to arm house pets, because they could be humans in disguise.