[Ronaldus Magnus]

Background checks help ensure you haven't committed a crime by selling your firearm to a prohibited person e.g. a convicted felon. Checking the firearm makes sure you aren't buying stolen property with a potential criminal history that could come back to bite you. FFLs at shows are already required to do the background checks. The law extends the requirements to private sellers too.

I'll assume that people who actually believe that kind on nonsense will only buy or sell cars through licensed car dealers for the same reasons. Even if they do, these cowards still benefit indirectly from private transactions they don't participate in. Direct private transactions keep wholesale and retail prices closer together than they would be if all transactions were mandated to go through third parties. Just imagine what you would get payed for a used car verses what you have to pay for one if you had to go through used car dealers. If private transactions for any good are mandated to go through only licensed dealers for that commodity, the market will become less efficient, net commerce in that good will decline, and consumers will loose out to the exploitive benefit of the dealers.

The government will also be able to collect them more easily.

[Eric in the Ozarks]

Its an attack on the right to own property, to buy and sell without government interference and the basis for a gun roundup list we know the Donks have in mind for sometime in the future.