Imo, this was an at best discouraging, and at worst infuriating, game mechanic. Here's why:
-Basically forced you to join the thieves guild if you wanted to sell stolen goods, thus removing choice, and choice is what really defines a rpg.
-Doesn't really makes sense, breaking immersion. A apple is somehow identifiable as stolen? Denied! Now let me sell some imperial guard's armor who I killed, and obviously is either stolen or the result of murder. Sell approved! o.O
-Inconvenient. I like to frequent the same shop out of habit and to build up that npc's disposition to get better prices...having to find a fence was just irritating.
The grand result was that I eventually stopped stealing altogether, because it wasn't worth the effort. I rarely vote for features to be taken out of the game, rather than added, but please axe this feature bethesda.
Thoughts?