1.5 to 2% of southerners owned slaves (3.5% max).
Only the rich could afford them. They were expensive.
But all those other lads were there happily risking their lives for the rich plantation owners. Because even though they could not afford slaves, and would never be able to afford slaves, they were so obsessed with the idea they were willing to die for it.
No.
Slavery was a flash point but the issue was states rights.
Most slaveowners understood that these people-as-property were an investment which depended on the continued health of the ones in chains. Therefore, they wanted to keep them fit, strong, and healthy. Seven-year indentured servants fared far worse. They were expendable.