Registration of tools is reasonably important for warranty issues, but as Leathermans at least can be dated by the stamp inside the handles, it isn't that huge a deal normally. The rest of the questions are a result of the manufacturer's desire to understand who is buying and using their tools, which is very important for the research and development of the next generation of tools. By understanding what types of folks are buying the tools, and what they are using them for they can design and build future tools that suit your needs more accurately.
If you could get 5,000 people to send in registrations with "I HATE CAN OPENERS" written on it, I doubt you'd see another Leatherman tool with a can opener.
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