Men, women, and children have been impressed into servitude since history started being written down.

I would also suggest that slavery and prostitution are more common and closer than we’d like to believe.

Raising a child to be a slave, part of a harem, or to be a prostitute, is probably much much easier than subjugation of the unwilling. They’ll never know the difference, if they’ve never seen the options.

Of course, if they fail to participate, or get used up, it’s quite easy to kill them and have no-one be the wiser. Much harder if you uproot them from families, where they might be missed, or maybe even looked for.

I would suggest that people aren’t only sacrificed to pagan gods, but also to the pride of those who would wield power over others.