Well the reply to your first sentence is "Who Does"? Second sentence I would add that apparently acquiring a "gun" is not that difficult in America today. What blows my mind is the murder culture. Today young men seem to be less willing to engage on an issue nonviolently and go straight for the "Hot lead" solution. The gun culture is not just a world of drug dealers, pimps and the unsavory. We are an unbelievably violent culture. What a shame.
On a somewhat related note that is both terrible and sad, a former SC State and NFL player is accused of killing 5 people, then himself. Name of Phillip Adams. AP source: NFL player Phillip Adams killed 5, then himself
And that may very well be the case here but there is no info for us to really go off and it's not unheard of for police to arrest and charge the only one standing from a shootout while the investigation is still on going.
This article, Domestic dispute led to ex-Giant Travis Rudolph’s murder arrest: affidavit, provides some detail about what transpired in the incident: