I still disagree. Both shields after Horn will cost 3m or more to craft/buy. All 61 weapons (most people jump straight from Ivory to Dreamwalker/61s) have mats that easily push costs to above 3m. Titan weapons (backbones + breakoffs) and Dreamwalker (original drop + inner mouths) are the two big ones.
People are cheap anyways. You're asking them to get something that
1. Doesn't offer much of a benefit (Horn works perfectly fine, you're only missing ~200 defense from not using a later one)
2. They don't want to waste time / money on an intermediate set (i.e. Pompush, 500k is not cheap in my book)
3. They can't afford as they were getting better armor (The shield is a moot point if you've upgraded to a Lv. 61 armor)
Edit
And I completely agree with RebeccaBlack on the skill thing. Also note that if they were using swords, you've got the damage gap to consider.