Horoscopes - Why Do We Need Them?

Somebody please explain to me how horoscopes work. Or if at all they work.

If all the 64 factors in the horoscopes of the bride and the groom match, does it mean that they will never have a fight in their marriage, that they will never have financial, familial, emotional trouble as long as they are married to each other?

If none of the 64 factors matches, then does it mean that their marriage is doomed, that they will never have children, and if they do that the children will turn out lousy?

Is the amount of misery or happiness proportional to the number of factors that match?

Was it in the horoscopes of all those people that died in the tsunamis, the earthquake, the floods in Mumbai and New Orleans, the London tube and the double decker bus, the twin towers, and the planes that crashed into the twin towers, that they would all die that day?

Was it written in their horoscopes that they would all die together, terrorists and passengers and people on the ground alike, in a fire ball, in the company of strangers, away from the protective embrace of their mothers and fathers, children in schools with concrete crushing their bones to powder, fishermen in rickety boats, on beaches, and city-dwellers in ditches and drains?

Was it written in Senthil's horoscope that he would die trying to cross a New Delhi street? If he had known that, would he be alive today if he'd stayed home?

Was it writtein in Vaishali's horoscope that her own father would ask for sex from her and that she would be raped by her own son, twice? If someone had told her that, would she have escaped what happened to her?

If your horoscope says you'll be successful, does that mean that you don't have to go to school or work?

What is a horoscope if not a convenient crutch, something to blame when things don't go as planned, as you want them to?