I've always liked the idea of not konwing what I'm getting into. Gads, it's been ages, but didn't AD&D have a percentage chance of identifying an item based on INT. Oh! I definitly remember the original Wizardry series letting Bishops ID things instead of going to the trading post. Wow, many cobwebs coming off there!
ON a parallel, how about just including more cursed items as well.
Not based just on Int, it was a chain of non weapon proficiences based on a Int or other stat check and skill role.
You had Appraising, forgery, gem cutting, history, armourer, weapon smithing, spellcraft.. basically if you had experience as a smith, an appraiser and some history knowledge.
You stood a good chance of knowing that the sword you found was silvered, was a relic of a noble family in the city nearby, and was worth roughly X.
But without spellcraft may not realise that the cold touch of the blade was a frost enchantment of some sort.
I'm all for cursed items, as posted alot these last few days.
Not going to read every post but I would say there is logic behind why you know the value of everything. You may start in jail but you had to have grown up there right? Or nearby, in a different province. So logically you are going to know that silver is more valuable than pewter, and that steel is more costly than fur. I see kids all the time buying things, even when they are like 5. Knowing the value of things in your region is something you learn your whole life. I have never bought a basic pack of silverware but if I went to a Walmart I bet I could guess close enough to bring enough money. The only things that should be more approximate are things like weapons, armor, and jewelry, things you need to know quite a bit about to know quality.
That is what descriptive text was for in P&P, the Dungeon master would describe what it was made of, where it was found, if it was shiney and looked valuable.
Since TeS actually names an item, then shows you exactly what it looks like, the cost on screen is not needed.
As all you have to do is see, "Silver Tankard", and anyone playing knows it's silver is a tankard, sees how big it is and what one looks like.
So they know it's worth something, if they don't then honestly my complete lack of education and misspent youth makes me smarter than most I guess.