Can you kill EVERYONE in fallout 3?

ok, in oblivion, you can kill as many of the npc's you want like highwaymen, then leave the area, return, and they spawn as a different variation. in fallout 3, if i kill 10 random npc's at the lincoln monument or in the super mart with the scorpion out front, will they respawn? that way i dont run out of bad guys to kill and can keep coming back to certain areas and have fun sniping people whenever i want.