Hi,
I didn't know that this concept was called a kitty. I was wondering what a cat had to do with a gift list
What HikaShop has is the wishlist system. With it, you can place products in your wishlist, share your wishlist, and users with access to your wishlist can purchase the products. The wishlist display will then display the product as being purchased so that others don't purchase the same product. It's useful for a wedding list, baby shower, etc. Note that the person purchasing the product will be receiving it so that they can bring it to your wedding, baby shower, etc in person.
So while it's close, it's still quite different from what you're describing.
To do what you want would require users to be able to create their kitty product. So it would probably require HikaMarket for that. Then, use the donation plugin to allow customers to enter the amount they want to pay :
demo.hikashop.com/index.php/en/hikashop/...t-page/donation-page
And then, with a mass action, with a PHP action, you could run a bit of custom PHP code to add the equivalent in points to the user account of the vendor.
That way, the vendor would then be able to use their points with the user points system to purchase things on the shop.