Why would competitors want to buy your domains extensions?
You may argue that by competitors buying your extensions, they may end up confusing their customers. The truth is competitors know exactly what they’re doing. They are buying your domain name and using alternative extensions, such as .net, .biz, .org and more. Ideally, this is a very smart trick to capture your customers. They bank on your customers entering the wrong domain name, and when they do, they are automatically redirected to their websites.
This explains why you need to buy multiple domain names to prevent that from happening. Buy numerous domain extensions, set them up and then redirect any traffic from them to your primary domain.