Hi,
What do you mean by excessive ?
A couple thousands of carts is not much.
A cart is just a few ids put together to link the products to the cart and the cart to the user.
Also, carts are differents from orders. The likely cause is that search engine crawlers try to index the add to cart links generating new carts.
So you can probably just ignore them.
And if you want to prevent them, you can modify the robots.txt of your website to disallow the URLs of the add to cart links:
www.hikashop.com/forum/checkout/891589-m...m-carts-created.html