1. The higher requirement makes sense, because they can have better enchantments on them.
2. STR based chars have an additional item slot as well (shields).
If you want to wear them for cosmetic reasons, you an just use your starter Sarong.
3. The only real reason why you would want to wear a high level no ability Sarong is because you want to enchant it. Since the stat requirements of the enchanted items don't change, it gets around the problem that players would enchant items and become unable to wear them afterwards.
4. You can get to crafting 5 very early in the game. Adding multiple +25% to all resistance enchantments to your equipment would just break the game balancing wise before you leave the first map.
5. Since many sarongs come with a +INT bonus and the max requirement is only 10 INT, you don't need to put many hard points into INT to use some awesome sarongs.
