The American colonists objected to the taxes the British Parliament levied on sugar and other staple goods because they believed it was to high and that they were being unfairly taxed. Their dissatisfaction is what lead many colonists to believe that separating from British rule was in their best interest.
The British had just exited a war with France and was in debt. It attempted to cover the costs of an expensive war by taxing colonists who wanted nothing to do with its economic recovery after a period of essentially self-governance. The motto of the day was "no taxation without representation."