24 Apr 2008 at 16:59 - 226
here is a way to find out if what you are asking is "right".
Would you like the action to happen to you?
I would answer no (And assume as such for the OP). noone likes to be cheated.
Would you want everyone to repeat this action to everyone else, all the time?
Again, no. If everyone cheated, lied, and took advantage of others than the system of market and trade would collapse as no one could ever trust anyone else and commit to trades effectively. (each side pointing fingers and yelling "LIAR") Taken to a real world scenario, it could lead to the collapse of the world economy if everyone blatantly lied about prices and always tried to steal exuberant amounts of money from their customers/partners.
Would you report this action to a societal and personal authority?
In this case, would you report yourself to a group/person who has authority of the well being of the game's market. No, as you would not want to risk punishment. In a real world scenario, would you report yourselves to the police, or any governing body that you had done this act? Again, probably not as you would not want punishment. Which shows you understand that others find the activity to be wrong.
Could you report this activity to someone who is very important in your life and whose opinion you value greatly (a family member, you Mother for example)? While in a "just a video game context" it would not matter of course, but put it into a real world. What if you swindled a man out of thousands of dollars when he sold his car to you, him thinking it was not worth as much as it was. Would you want to tell your mother? (very personal and thus varying question ,I know but it shows how we internalize guilt even if we don't outwardly accept it)
and there ya go.
if you dot want it to happen to you. And you don't want anyone else to do it, and you don't want anyone to know that YOU specifically have done it. then its wrong. For more info on this method google Immanuel Kant, and "The Categorical Imperative". beware though, the guy's books are hell to try and read through.
tl;dr : learn patience and attention. please try and read it.