Sometimes other people feel sad, either because they're feeling under the weather or because they've lost their wallet or even their their arm during a tragic misunderstanding in a game of monopoly. As a general rule when people feel down we all try to help them feel better. It's a societal rule. Without societal rules society would fall apart and nobody would ever deserve chocolate pudding.
I find people very demanding. "Do this, do that, be quiet, don't eat my pudding, put down that knife, tie it off with a tourniquet, drive me to a hospital, what do you mean we're stopping to buy ice cream?" Today's card? Send it to anyone and they'll probably just GIVE you their pudding. It's only reasonable, really.