Firstly, the lack of stylish, unusual suspender belts on the market that actually had the ability to hold up stockings.

Secondly, how to wear stockings with a corset (which are after all, the most practical option apart from the most aesthetically pleasing one) which is being worn over the clothes. Suspenders attached to a corset are stunning but no use if you wish to wear it over a skirt. In that case you need a separate belt, and how much more appealing to have one that matches your corset
 

Of course, you don't need a corset to wear a Crikey Aphrodite suspender belt. They look equally good with a bra or camisole.