Warranty registration cards and homeowner obligations

Are homeowners obligated to return their registration card to protect their warranty rights?  Generally this is not true - and prohibited in a few states, notably California.

For warranty purposes, the only information a manufacturer needs is the homeowner's name, the date you purchased the product, its model and serial numbers, and a way to contact you in the event of a product recall. 

But the registration cards usually ask you to provide much more personal information, including marital status, the size of your household, frequency of travel and favorite activities. Product owners are not required to answer personal questions to be protected by the warranty.  (NY Daily News) More...