Of course Vogel is right about game balancing but in the real world no such thing occurs. People actively "collecting" money want it because they are either greedy, want more power that goes with it or both.

If we transpose the real world to a fantasy RPG not only paying money for learning martial arts makes sense:
Weapon dealers would be the main reason the land gets invaded by monsters or other "races" to get the natives buy more weapons to defend themselves.
The military-industrial complex isn't wholly out of the question in Middle Earth!
 

Well, if I were willing to risk setting up a weapons shop right on the edge of destruction instead of cowering in safety, I'd probably charge premium, too.

As far as STARTING a conflict in order to better one's own position... wow, nobody in an RPG would ever do something like that, would they? (*evil chuckle*)
 

Vogel makes some good points, but he gets others wrong or distorts the situation. Being former military, specifically a Marine like he used in one of his examples, I can say that yes, bartering absolutely occurs - when things are peaceful or you are in camp. If we are heading into combat, or are IN combat, you don't say "F*** you! Pay me!" You give them the night vision batteries if you have extra, or the can of grease, or ammo.

You may ask for something in return that you need, but if they can't spare or don't have anything in payment you don't tell them to "F*** you! Pay me!" After things are settled you may ask for a favor in return or arrange a form of payment, but after you've dealt with the situation and again not necessarily.

I understand price gouging in RPGs and by merchants, even in dangerous times. Hell, I understand a merchant asking you to rid an evil from the town not loaning you a sword - you may die, you may run off, you may be the sixth shmuck to pledge to get rid of the problem, etc.

HOWEVER - when the life of the merchant clearly and without doubt depends on you succeeding and you ask them for a better sword or armor, or healing items - why in the name of all that's holy would they charge you or gouge you or refuse to shave some gold off the top if you're short?

Final Fantasy X comes to mind, where you are in an airship that is attacked by a giant monster intent on destroying the vessel. You have to go fight it to save everyone aboard - including a merchant who charges you an arm and a leg for equipment. His excuse is that he is "confident in your chances of success". "F*** you! Give me that f***ing sword!"

Worse is when your character or party are friends with a merchant. You've been buying from them the whole game, doing them favors, rescuing them, and have proven to the ENTIRE world at this point that you are the last hope remaining. They'll even tell you that. Now you find your friend the merchant (who's child you saved - maybe even TWICE) outside the big bad final battle for the world, etc. . . . and he charges you more than he ever has before. I couple thousand gold short on that 200K uber-ultimate weapon he has in stock? "F*** you! Pay me!"

Excuse me? No credit? No loaner program? It could even be argued that if the world truly is at stake, and the merchant is withholding a weapon that drastically improves chances for success, he has just become an enemy to the world every bit as nasty and interfering as those monsters blocking the door. If the hero is even the least bit practical or morally gray, they are VERY likely to take what they need by force, and no one in the world but the merchant would complain.

So I would say, "I don't care if you want me to pay you, I'm saving the world!"
 

One quick point: There's a difference between profit and profiteering. Not all business taking place in and around war zones is the latter. Something to remember when thinking about the depiction of military-industrial complex businessmen, mercenaries, and so on in fiction.

That said, I'll second what LWR said (Ex-Army here). You'll barter in the rear, in garrison, when things are quiet. The occasional supply type may even gouge in garrison ("Oh, you're light on PLL, and the inspection for the Battalion Change Of Command is tomorrow? Really? Well, I'm sure we can...come to an understanding") although that's rarer since what goes around tends to come around. But no, you're not going to tell guys going outside the wire on patrol, or going on a mission "Fuck you, barter with/pay me". You're certainly not going to do it mid-attack (as in the FFX example mentioned earlier).

In a similar real world example, there was a gun shop just down the way from the North Hollywood Bank that was the site of the infamous "North Hollywood Shootout". When the SWAT team was delayed and the cops found out that their targets were too heavily armored and armed for their service weapons and shotguns to be effective they ended up going to that gun store. The owner provided them with hunting rifles and slug ammunition for their shotguns without any "Fuck you, pay me!" or even "Better fill out your 4473!". They didn't end up using those weapons to drop the robbers, but it illustrates the real-world principle pretty well.