In the USA there's a thing called the Magnuson-Moss Warranty Act. One of the things it does is forbids anyone from requiring service be performed by the manufacturer or authorized agent unless that service is provided free. Since Suzuki doesn't provide free warranty service, anyone can do it, including the owner. You would be wise to retain records and receipts of what you do in the event you need to make a claim though.
Another cool thing the MMWA does is it allows you to modify your product and the manufacturer can't deny your warranty claim unless they can prove what you changed was the cause of the failure.
If you want to read up on it, there's tons of stuff on the Net on the MMWA.