The South saw the North as hypocritical on the slave issue because the ships carrying the slaves were often captained by New England sailors and....

the northerners smoked tobacco.
slavery was legal in the North even as late as July 4, 1776. many northerners owned plantations in the South. the northerners wore cotton.

1 answer

The South saw the North as hypocritical on the slave issue because slavery was legal in the North even as late as July 4, 1776. This perceived hypocrisy was rooted in the fact that while the North was increasingly moving to abolish slavery and criticizing the practice, they had historically benefited from and participated in the institution of slavery as well. Additionally, many Northerners profited from industries such as textiles, which relied on cotton produced by enslaved people in the South.