Colonists hated the law during the stamp act because it was a tax placed on goods. This also increased the cost of many essentials that were not available from other sources (no taxation without representation). For example: before the stamp act bread costed about a nickel or so. But after the stamp act, the cost of bread rose to $1.00 a loaf. This dramatically effected all of the colonies.
Because the money was for England, and not to be used for the benefit of the Colonists. Not to blame the UK, but to point out that when a nation colonizes a land, they are entitled to some financial prize. The Colonists rebelled, which was their privilege. The rest is history. Those with the most bullets won.