The problem, like any game economy left unchecked, is that they keep adding ways to make money and not enough sinkholes to get rid of large amounts of it.
Think of World of Warcraft and its 25 dailies limit. 25 quests with tons of payout with very little money payout in armor repairs... yeah over a year that's going to mean you've a lot of money out there not being eradicated from the game. And simply passing it along to someone else does nothing to the supply of money.
Think of the daily login rewards we get. You get lots of credits, plus the money you can earn from dailies and running instances over and over, with very little repair costs. Yeah it's no wonder that people are running around with 15 million credits in a month and then put level 10 items on the GTN for 150,000.
They've busted the economy up and the only real way to solve this issue would be to wipe credits in excess of 'x' amount. You can bet that this won't be an option they'll pursue.