What were some reasons given in favor of continuing the practice of slavery? Southerners stated that slavery was both moral because it was practiced in biblical times, and financially necessary for the economy of the country. African-Americans were not interested in competing for jobs with poor white Southerners, and would rather be slaves. Southerners stated that with factories widespread in the South, slaves were needed to work there. African-Americans liked being slaves, so the practice should continue.