First, I wouldn’t rely on a realtor’s advice from 1998 to make insurance decisions.
Second, I tend to agree along the same lines as desmond. Depending on your other assets it may make sense to buy earthquake insurance under the following conditions:
1. You have substantial equity in your house.
2. The cost to replace the structure is significant with respect to the value of the property (land) and/or with respect to your non-RE net worth.