If you hit two balls with a spin attribute of say 4 and 1, with an iron with a spin attribute of say 0.5, then the results you get will probably be pretty similar. But if you hit the same balls with an iron with a spin attribute of say 4, then the results you get will be noticably different.
The balls are not the same, but the clubs you hit them with, make the difference more or less noticable.
With high spin clubs and balls you can make shots back up (reverse) on the greens, which is fun, but you can find yourself back on the fairway if you overdo it.