Final answer:
The Stamp Act was deemed unfair by colonists due to its wide-ranging internal tax, the perception it was only for British revenue, and that it was imposed without colonial representation in Parliament. It also eroded the financial influence of the colonial assemblies over British officials.
Step-by-step explanation:
The Stamp Act was seen as unfair by the colonists for several key reasons. Firstly, it imposed an internal tax on a wide range of printed materials that were essential for daily use in the colonies, such as newspapers, legal documents, and playing cards. Secondly, this act was perceived as a mechanism primarily to generate revenue for the British government, rather than to repay debts from the French and Indian War which had benefited the colonies.
Most significantly, the tax was imposed without giving the colonists any direct representation in the British Parliament ('no taxation without representation'). Furthermore, it diminished the financial leverage that colonial assemblies previously held over royal officials, as it gave salaries directly from Britain, thus eroding a layer of the colonies' influence on governors and tax collectors. This sense of injustice led to the first major unified colonial protest against British policy, underscoring a desire for equal treatment and self-determination.