Either we accept the idea that it's moral that someone needs to effectively be a slave to the system to enjoy basic rights such as a roof, food and medical care, or we don't. Age shouldn't play a role in this.
With you on the struggle against modern slavery that is rampant against adults, let's not make it a child/teen only concern, but until then we certainly need to distinguish adults from the to become grown up men and women.
There is a reason we have different moral, legislation and rules w.r.t the treatment of children. That applies to employment, intimate relationships, sales of stimulants, ability to hold a credit cards etc.
All down to the fact all the way to being a teen, humans are still in the process of brain and experiences maturation to take on society and independence on their own, without special protection.
Ah well, who am I kidding? (shovels another load of babies into Mammon's burning maw.)