I don't think any of us know WHY some people seem to have more blessings than others, but I don't think there's one simple answer that'll sum it all up; rather, it's a combination of many things. Definitely I don't understand why some people are able to have children, while others can't -- no matter what medical extremes they attempt. I don't understand why some children are born with healthy bodies and others are racked with terrible diseases from birth. I don't understand why some of us are born into America with so many opportunities, yet children in so many other places are born into political turmoil, famine, and ignorance.
The term "blessings" definitely has religious overtones, so I'm thinking of Biblical references to illustrate:
The Bible does talk about "sins of the fathers" being visited upon the children. I remember being confused by that as a child, but now I see it as natural consequences. For example, my father was an alcoholic. My brothers and I suffered many negative consequences because of his actions. it wasn't that God did those things to us; rather, our father put us into that situation. None of us WANT to hurt our children, so that's a strong reason for us to stay on the straight and narrow. Sometimes physical suffering comes from natural consequences; for example, poor diet and lack of exercise can lead to many diseases. But we tend to understand that type of thing better. It's "born with" stuff that we can't comprehend.
And sometimes what appears to be a curse turns out to be a blessing: Think about Joseph. His brothers sold him into slavery and told his father that he'd been killed by wild animals. In Egypt, however, he distinguished himself and ended up convicing the Pharoh that they should store up grain against a coming famine. When Joseph's own family arrived in Egypt, seeking food, he was able to save them. If he'd not endured the hardship of being sold into slavery, his family would've been lost.
Another example from the Bible -- it's in the gospels, but I can't remember which one: Walking with Jesus, the disciples saw a blind man, and one of them asked whether it was his sin or his parents sin that caused him to be blind -- obviously, they had the impression that all bad luck comes because of sin. Jesus corrected them and said that the man was made blind simply because this condition would bring glory to God, and then He healed the man. Does this seem "right" to us? Maybe not, but all the people who saw him healed (and the people who read about it today) recognize that God has the power to do things that we cannot.
Next, I'm thinking about Daniel's three friends Shadrack, Meshack, and Abendigo (I'm sure I'm waaay off on those spellings) who were thrown into the firey furnace because they wouldn't worship a false god. As they were thrown in, they said that God COULD save them IF he chose to do so -- and He did. They showed that they understood that sometimes God chooses to save a person, sometimes He doesn't. The reasons are beyond our understanding, but I'd suspect that sometimes people die simply because they've accomplished the tasks God wanted them to do on Earth, and He's ready for them to come to Heaven.
Next, God isn't the only one who can give "blessings". Satan and his demons have power to make GOOD things happen too. They can help a bad person to prosper. Why would they do this? Simple: It causes confusion, it makes us wonder WHY such things would happen, and it gives us the impression that blessings are rather random.
My last example: Jonah. Sometimes we suffer hardships because we're running away from God's will. Jonah was told to go to the city of Ninevah to preach. He chose to run away in the opposite direction, and God "caught him" and had him swallowed up by the great fish. That had to be a horrible experience, but if he hadn't done wrong in the first place, he never would've been in that situation.
The list of examples of hardships and blessings from the Bible could go on and on, and the stories vary widely. I think that means God treats this person one way and that person another way for reasons that He understands. I'm sure that each of us is put into whatever circumstances are good for us -- good for us as in help bring us to Him in the long run -- but these things aren't always the things we'd choose.
I also know that the Bible says that those of us who have greater blessings are held to a higher standard -- we are expected to USE those blessings to do good for others. If we don't use what we're given, we'll have to answer for it later.
Since we cannot control whether we receive blessings or not, the real question is, "What are you doing with what you've been given?"
It's more a recognition that life is a crap-shoot even when one works hard and plays by all the rules.
. I don't think of being blessed as being worthy, entitled, lucky, self-righteous, etc., rather for me it is simply being ‘thankful’. 
