Now we see why
The Protection of Lawful Commerce in Arms Act is no doubt wanted because of stupid lawsuits like this one from a Brady Presser against Cary Jewelry & Pawn:
In November 2003, Van McQueen and Matthew Grant went to Cary Jewelry & Pawn to buy a firearm. McQueen planned to purchase a firearm as a straw buyer for Grant, because Grant was a felon prohibited from buying guns, and in return Grant promised to buy McQueen a beer. McQueen was mentally deficient and was obviously intoxicated, and the shop’s clerk refused to sell him a gun. Three days later, McQueen returned to the pawn shop with Grant, again wanting to buy a firearm. Although his home address was a local mission, McQueen had $120 in cash to buy the weapon. This time, even though the same clerk who had seen McQueen intoxicated three days earlier was on duty, the shop completed the all-cash sale. McQueen then transferred the shotgun to Grant, who used it to shoot Investigator Tucker in the face, killing him. Grant was arrested, convicted of first-degree murder and sentenced to life in prison for the murder of Investigator Tucker.
I see no evidence that the dealer violated the law. This lawsuit’s only purpose is to put the gun dealer out of business.