We’re not greedy enough.
If someone stole all the pennies in your house, not the quarters, not the bills, not the credit cards, just the pennies, would you characterize that person as greedy? It’s not greedy, it’s petty and stupid.
But aren’t we in the same position? Even if you had one hundred billion dollars (USD), it’s still so small. And even if you lived for one hundred twenty years with that amount of money from start to finish, it still would be so little.
On the other hand, in heaven, you could have a piece of property the size of an entire planet. You could own a galaxy. Women (or men) more beautiful than anyone who has ever lived would fawn all over you. You would never feel ill for a second. You would never be hungry, never be thirsty.
If we were really greedy, we would be doing whatever it takes (i.e. prayers and fasting) to get this great reward. Otherwise, we’re just stealing pennies.