Ok, so before you just post "NO WAY!!" actually listen to what I have to say..
I find it a terrible idea when there will be not a singe kioka or omni egg left, so I have come up with a solution: eggs :)
Let's say two of my uilis, Whirlaway and Merla for example, are very healthy and happy pets (which they are of course). So one day they decide to have an egg! This would be a totally random event and can only happen once in the parent creatu's life. Also, only adult creatu over the age of 50 (always a good number) should be eligible to produce an offspring. Also, like I stated above, this is totally random! It's like finding a canadian nickel on the sidewalk here in Dallas, Texas. Totally random and a rare find, but all the same possible.
Remember:
~ This is totally random
~ you must have a healthy, happy male and female creatu of the same breed and over the age of 50 on your profile
~ Only happens once in the parent creatu's lifetime
Edits: Pets should have to be more like, 100 days old to "breed" and there should be a charge for CS pets.
So, what do y'all think?