Most people do the right thing when they are presented with someonelse's mistake. We have all had the chance to do as he did but many others choose to correct the mistake and either pay the fair price or not buy the item. If you are given too much money in change do you pocket it or give the extra back? I always give the extra back. I suggest that taking advantage of others is nothing to brag about and he would have been better to keep his "bargains" to himself.