Well, now that we have modern ways to turn high voltage DC into low voltage DC, the technology might change. There is discussion of long distance transmission of DC from for example wind farms to cities.
However back to your question:
The power losses in transmission are proportional to the square of the current, i^2 R but the power transmitted is i V. Therefore to minimize power losses along the transmission lines for a given power i V at the end, you want to make i small and V big. That is why those fancy transmission lines you see in the country between cities and power plants are so high and have such big insulators, they are very high voltage. However you do not want that high voltage at the plug in your house. Therefore the voltage is stepped down by transformers for local distribution. Transformers do not work on DC, only AC. That is the long and short of the argument historically.
Household electricity is all AC. Early on Thomas Edison pushed for houses to use DC. Why did AC win out in the end? What do you suppose was Edison's motivation for preferring DC?
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By the way DC is really handy if you have a battery involved :) I do not think Edison visualized the network of electrical transmission that evolved and therefore the need for transformers. Note that your car works on DC as do virtually all electronic devices (it is rectified from the AC that arrives at the meter outside your house). Even your modern car generator is an alternator these days and the AC is rectified to DC before distribution to the radio and battery and lights etc.
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