That is because this is the information that the DMV makes part of "public record"....
Here is form INF-70, read the second paragraph on page (1)... It specifically states that the residence address/telephone number will not be released to an individual who asks for it. That IS confidential information that is protected by federal law.
Also, read second paragraph on page (3) under Confidential Residence Address Information... Again, same as above!
The "insurance reasons the DMV qualifies are described under Section D: "Purpose of Request - Permissible Uses" as follows:
Insurance Purposes: For use by an insurer or insurance support organization, or by a self insured entity, or its agents employees, or contractors in connection with claims investigation activities, anti-fraud activities, rating or underwriting
My guess is you don't qualify as being one of the above...
You may find that the only way to get the information you're seeking is by getting an attorney to submit a request on your behalf by filing a form INF1161E