This is a real Game-Breaker, since players can drop the Perception of every enemy to 1 with 9 cheap bottles of beer, their strength down by 3 by giving one enemy Buffout and waiting 6 hours for the hangover, diminishing their Action Points by addicting them to Jet. The most widely abused bug in Fallout 2 gives the status effect of a drug used by/on an NPC to every NPC in that category (e.g.You'd still get the upgrade, and can use your stuff for the other upgrades too. then opening the barter screen and use the 'drop item' function on your money and combat armor.

This could be averted with some doctors (Johnson in Redding for one) by agreeing on an operation, moving the conversation to just before it's about to start.