Huntin' Shack

The Huntin' Shack is a gun store in the North Plaza. It contains rifles, shotguns, and handguns, all of which may be freely pilfered. At the beginning of the game it will be occupied by psychopath Cletus Samson.

If Cletus is not defeated after two days, he will be killed by the three survivors that take over the store: Brett Styles, Jonathan Picardson, and Alyssa Laurent. They are hostile, and will open fire upon Frank unless he shows them that he means no harm.

The most likely reason for the three survivors not showing up on the third day if you killed Cletus is because Cletus kept clearing out the zombies that congregated outside the store. Once Cletus was killed, there was no one to keep killing the zombies that inhabited the are, which would mean that the three survivors probably never made it to the store and were killed because of the high amount of zombies in the area.

Trivia
For gameplay reasons, Frank will be able to get three shotguns and a restricted amount of snipers and with set ammo limits. Handguns are infinite because of their availability and being weak. They can be gotten via crushing the square display in the center of the shop or the glass displays in the back. There are un-gettable guns all around the store and no ammo since Frank cannot reload guns, just get more.