well if they saw a preview of the fat man....then well....
Me: "No listen man it's really fun, look if you like big boom there's this one gun that shoots a small nuclear bomb!"
Friend: "No way?! Where can I get it? I want it! Is it awesome? AHFGJGHJDFG!"
m: "Well... first you need to escape from Vault 101..."
Later...
f: "K well i'm in this Megaton place, now where's the nuke launcher"
me: "Fatman? Well that's kinda later in the game but if you keep playing you'll get to it maybe by tonight."
next day
Friend: "Yeah man this game blows, stupid raid guys keep killing me at the grocery store and I still didn't find the Nuke Launcher"
and then I died because I facepalmed myself so hard my brain flew out the back of my head.