Being ignored doesn't necessarily imply being broken. These people might be close to being max, it could be the reason why builder potion are ignored, in that stage those people could have eyeing training potions or anything that can speed up armies other than fast forwarding upgrade of storage or collectors.
The price was increased for medals, due to it being by far the best value initially.
If people are ignoring it in clan games, then unless they are near maxed, they are rather shooting themselves in the foot.
For buying, IMO only two things are generally worthwhile from the trader - training potions and book of heroes. But when they are free from clan games, builder potions will take precedence over any other potions or resources. Runes and books are usually more valuable.
Thanks TerMinus Prime for the sig pic