In English, when you say someone is greedy, it conjures up thoughts of someone taking everything in sight, leaving nothing for others.
In Russia and Ukraine, greedy has a different connotation. A greedy person is someone who won't buy something because it is overpriced, or if they don't want to spend their money on something relatively useless. Being called greedy is a pretty big insult, and once a woman thinks her man is greedy, there's no reason to continue dating them.
In the USA, being frugal and spending your money carefully is considered a good trait. When an American man dates a Ukranian woman, he can get confused when a woman looks down on him because he won't spend money on something he'd like. This is a matter of culture clash. In the former Soviet republic, when people had extra cash, they'd spend it on niceties. Holding on to your money makes you look like Uncle Scrooge. When you want something, and all the bills are paid, you'd buy it...even if it was overpriced. There are a lot of folks who like to show off a bit. The Ukrainian women I've dated may not have had a lot of cash, but they'd always have the latest electronics or the latest fashion.
Should you be engaged to a traditional Russian woman, you should go out of your way to make her family feel you're a good fit, and that you're not 'greedy'. Flowers are nice, but never bring a dozen -- that's specifically for funerals. Stick with an odd number and you'll do well. If you make the mistake of saying you'd like to buy something in front of her, you're pretty well stuck buying it.