It's not a greed driven thing I think, I can't speak for anyone else but for me personally I find the cap too low for the plain and simple reason that the dailies will get you to your relic cap in far far less than a week, ergo they put in a cap which is so much lower than the actual relics that you would earn even if you only do half a week worth of dailies.
I'm not a dailies man, really I'm not, I'm not a fan of currency caps, but if they put one in they ought to AT LEAST get closer to the amount of relics that you COULD earn in a week, I'd already be more than happy if they'd cap it at 6 days worth of dailies.
There are around 17 dailies if I'm not mistaken, most of which giving 7 relics, 4 of them give 12, you end up with a total of 139 relics every day, or 973 relics in a week, 973!!! And remember, we're not counting the weekly missions here.
If you're gonna offer a potential of 973+ relics in a week then WHY put a cap at such a low number as 250? It's just too big a difference.