Imagine: your party is already walking due to the heavy overload. Your strength buffs run out. You drop some chain mails to be able to walk again. One more room in this level, a chest even. Close. Ah, your warrior has one more "Enlarge Person as a level 2 wizard" spell from his ring, which is enough for 2 minutes. You can even pick up the chain mails you dropped. Back outside: your strength buff runs out again. Noooo! But you made it back.
That's why I make sure to sell everything I don't need, whenever I get the chance.
Haha. Yeah, I don't play the dungeon game. I got so tired of combat I'm on a break at the house at the edge of time. I hope to get back into it next weekend.
Kept tons (almost literally by the end game) on me at all times. Bags of holding were great for that. There's no penalty until you pass the first notch, and even then it isn't a large one.