This "problem" is probably partly due to playing on Normal difficulty, as presumably you need them more on the higher levels to survive, but what do people do with these things? Sell the lot?

Am up to level 12 now, and got a couple in inventory...This doesn't even show the wands because the UI isn't big enough, but I have about 3 lines of those too. Recently I've been glugging down cure light wounds potions just to get rid of some of the weight, but we keep picking up more (and it's easier to use Tristian). Combined it must weigh quite a lot.

Loot whores run into all kinds of "problems" :D Saving it up for a rainy day that may never come, and largely forget about it anyway during combat and adventuring. Then go looking through the loooong list for Restoration scrolls or potions, but we don't have those, and certainly not in ample supply.

it's actually lower difficulties where scrolls and such are better. Mostly cause it can do at least something on lower ones. For unfair it's a waste of action to use.

Buff scrolls and pots do have a big use, since they can be used instantly from inventory if you were ambushed. That's a big use case. Some wands give you stuff out of your class, so that's useful. Heal wounds wands are ok too for obvious reasons.

Attack spells/wands/flasks are just not good enough and wand DC sucks, so those go to vendor.

Actually used potions to try to get Amiri to win in the one-on-one in the main story in the barbarian camp. She sort of did, but apparently it didn't matter.

Short of rare cases like that, though, looks like it's simply more vendor trash. Wish there was a button we could click to put a whole stack into the vendor UI without getting the pop-up thing for how many we want to sell. Would have saved quite some time.

(If this is a feature, please tell me how)

Is there any use of the cabochon rubies (from Vordakai's tomb) and the toy knight and toy dragon from early game? If not, I may as well just sell them.

Would have been amusing if I could stuff those things into Tristian.