Salvatore Lappus is one of the characters in Jagged Alliance 2.
He is an airport worker like Pablo Greco who appears if you kill Pablo and substitutes him to manage the supply of goods, including the online supplies from Bobby Ray's Guns and Things.
Unfortunately, he is even more unreliable than Pablo. Not only is he going to lose small amounts of stuff, but a lot of times, he loses the entire shipment! Threats have no effect on him as he does it through sheer incompetence.
After killing Salvatore, no one will be able to settle the further shipments to the airport. No more guns and stuff from Bobby Ray's.
So, don't kill Pablo :)