Child labor was the norm under every social order before the industrial revolution. What became wide-spread with the industrial revolution was children laboring in factories as opposed to farms and workshops. The use of children in factories was actually pioneered by socialists, and not found shocking because it was the norm for children to work somewhere. Had child labor been outlawed in the early days of the industrial revolution or under previous social orders, the result would have been for most of these children to starve, because people had more children than they could actually feed.
(Note that the Bear is in a pre-industrial society.)
Eventually, in the context of a market-based economy, technology lifted the standard-of-living to the point that it became possible to outlaw child-labor without a visible die-back of children. (I've not researched how large the unrecognized die-back was in the earliest stages of these legal changes.) Child-labor was not simply outlawed in one pass; for example, it continued to be the norm in agriculture for a long time, and the legal status remains different in those cases.