I've come across that issue to. I've looked at title work and it says it's in the name of one spouse only, but then I'll go to the mortgage and it's got both spouses listed on it. The Title Company has said it's required because we are a community property state. We've argued too and they've refused to budge. They have this language in their title policy:
"The proposed mortgage should either designate the subject premises as non-homestead, identify the mortgagor as unmarried or be joined in by the spouse of the mortgagor."