Not at all. You assume that paying less is more rationale. I posit the idea that it is more rationale to not waste time doing things that are not enjoyable.
A good credo to live by.
But for argument's sake, the time you save is illusory. Why? Because it took you time to earn the adena to purchase said item. You are simply shifting the negative impact so that it SEEMS like less of an overall waste in time to you.
If we looked at the grind and adena earned in terms of wage hours, we would eventually conclude that you would have to farm X amount of hours in order to earn enough adena to make a given purchase. Even if you are out "hustling" in the market, the principle is the same. Farm less than those hours and you don't earn enough to complete the purchase. Farm more than those hours and you increase your income, but it's still at a personal cost to you in time.
So to buy an item for more than it's actual cost means that you are effectively farming for longer hours, for less value. In short, you are wasting time AND money. That wouldn't be more enjoyable, I don't think.
Obviously, this is not a hard and fast rule, since other variables factor into it, but you get the point. And yes, once again I'm making an assumption: no one enjoys the grind so much that they'd be willing to work more hours for less returns on their labor.
That is very true, but think of it this way.
If the idea of playing a game, and especially a game like an mmo, is to maximize what one enjoys and to minimize what one doesn't enjoy, then it stands to reason that any player would try to maximize the enjoyment in what he/she chooses to do.
To this end, one should seek any way to make money that one enjoys.
I have two ways of doing it. I do some overenchanting but make sure I don't exceed that point of no retun where you are actually losing money (for example, I recently spent 90 million on enchanting 3 DC robes to +6. I failed on one and sold the other two for 105 million each)
I also try to find items that are highly sought after by players but that I can buy and resell for a minimum of 2 million adena + for each. Essentially "playing the market".
I find this enjoyable to a certain extant and feel that it is worth my time.
So I have wisely spent my real life money for game enjoyment.
Now that I have profited in both enjoying my time spent and also making some money I can now apply that newly made money to something that I need.
there is the +5 wand of instant killing. I can either spend a million hours in an area where I don't want to be with the hope of a drop or spend all those extremely tedious hours gathering mats with a 60% chance of success or I can purchase it for double what it probably is worth and move on to something else that I enjoy.
Now, getting back to your original post, I'm not sure if I have benefitted from knowing more (in the areas that I could possbily know more) about the game than others.
I have however taken advantage of the luck of others when it comes to them selling things they made, especially things like shots.
So, for instance, if I find somene selling shots for far less than any other shop, I will buy all their stock and sell for the going rate. this way I spend less time making them and I just take the small profit as it comes.
However, there once was a time when NC changed the amount of items that were needed to make shots so the price went up.
I raised my price and was one of the higher in gludio. 2 other dwarves wanted to raise the price even more and pm'ed me to ask me if I could raise my price to what they wanted to get so that no one could pay for any less. Essentially price fixing.
I felt that amount that they wanted to get was unreasonable so I refused. I have no problem overpricing but I do have a problem with gouging someone. Some might not appreciate the difference but I feel there is one.