First of all, you're acting like cash trades flat-out correct all budgeting mistakes with no consequences for the owner who made the mistake. That's incorrect: the owner pays for his mistake by having to give up a prospect, or sometimes more. Are you against budget transfers, too? That takes away some of the importance of budget day, too.
You're completely misinterpreting my consistency argument as well. I'm in no way arguing that all trades are the same. In fact, I'm arguing that YOU'RE the one treating all trades the same, by grouping all cash trades together rather than looking at each based on its merits. Just as you wouldn't group all player trades together, you shouldn't group all cash trades together. Each is different, and each needs to be looked at based on the merits, fairness, and effects of each trade.