Apple often features apps of poor quality and it's not always clear why (e.g. games with 3 stars developed by big names or indie apps not working as they promise). So, yes, I understand why people are surprised.
You are considering the inverse of the matter. The post is about a high quality app being featured. My comment was intended to say that it shouldn't be surprising when a quality app is featured.
I think, without any proof to the matter, that some of those are sponsored advertisements, especially the ones from larger development groups.