Any company that offers a transferable warranty requires proof of original purchase
Perhaps Raquel refers to "out of warrenty" service - it is a fair point if you buy used then it is better to go with a manufacturer that supports their products irrespective of when, where or how you acquired the product. And some pro speaker manufacturers do follow this philosophy. Few, if any, consumer speaker manufacturers are able to do so because they outsource most of the parts and after 5 years or two or three new models/versions later ....no more spares.