If the products have been deleted, this is completely normal and the correct way to tell Google and other search engines that the product is no longer available.
The links that lead to 404 messages will be crawled by Google and will slowly be removed from the index.
There is plenty of information on the web about this, I recommend you sign up for Google webmaster tools and keep an eye on any messages for your site.
Showing this error for users can be a bad user experience.
Since these are disabled products and not available, a 404 error is better than leading to user frustration that they cannot purchase a product that is not available.
Depending on the traffic to your website, these links will be removed.
Also important, make sure that these links do not appear in your sitemap.