The elimination of a free market is the first step in Socialist theory, along with the nationalization of independent business.
History has taught us that this is modus operandi of all dictatorships wishing to create an utopian society of 'equality'. It is classic Marxist theory, with a little Stalin muscle to back it.
Yes, this is just a game, and hardly comparable to the Cuban Revolution, Soviet Russia, or Kim Il Sung's regime, but in the end it is human nature and emotions that will be at play. So, here's what will happen:
By setting a price band, EA has manufactured the end of two things: Inflation and Deflation. The inflation of goods (players) has been capped to a point where there is no longer profit to be found in investing. Why? Simple capitalism. The only reason anyone buys stock is the belief that every company has the potential for a golden breakthrough, and one will own the next Microsoft or Apple. Investment is the belief that an expenditure will provide returns with Fifa 16 coins xbox one. But there is now a visible cap to all ROI (Return on Investment). This means that everyone knows a player will never go past a certain number, and this eliminates the promise of investing in players. Face it, No one is going to buy more than one player X when you know that every other player X on the market will be available for comparable price. No longer will there be fluctuations, as there is no room to fluctuate to.
so what will we see? Simple: Hoarding of personal use goods. If people buy a desirable player for market cap (as is the only way anyone selling that card will be willing to list it), they will feel no need to list it on the market, as they know they will not be able to sell it for more than they bought it for, and with the 5% tax, there is definitely a penalty for engaging in market trade, we will see the continuation of "extinct" players.
Without inflation there will no longer be an urgency to engage in market trading. People's Fifa 16 coins will be much more precious, as everyone will be reluctant to take a loss of their hard earned coins to make experiment teams, vanity teams, etc. We will all know that a loss is unrecoverable by market trading.
At the other end we now have a cap on deflation. This is potentially more devastating to the poorer users of the game. There will no longer be the natural curve of market prices on used goods. towards the final 3 or 4 months of a release titles life span, prices of the midrange players (think Gotze) used to slide down till they were in reach of more 'casual' players who haven't been accumulating wealth via trading (which will cease to exist anyway) or via massive number of games played.
With a now minimum price, that is far above what the natural deflation would have been by the end of the games cycle (when untold thousands of Gotzes have been issued), all you will see is those thousands of Gotzes on sale for minimum bid, and if you're the seller, you have nearly zero chance of simply selling the damn thing, as you can no longer undercut competitors. Of course buyers at the low spectrum will NOT be buying, because they will not spend that much coin on what is no longer a player worth his price.