[development] Turning custom_url_rewrite_* into hooks?

I've working on a custom module for a project that makes use of custom_url_rewrite to open up linking shortcuts through the url() function and I was wondering if there is any specific reason this functionality isn't a regular hook? I know I could probably use URL aliases for what I'm trying to do but requires me to not have to worry about managing hundreds, possibly thousands, of URL aliases just to open up this type of functionality. Maybe I'm just mis-using this functionality but it seems like it might be worth while to consider.