Why insist husband and wife be present?

Basically the title. Had a guy come door to door to my parents house asking if they wanted a quote and when the boss called he was super insistent telling my dad he could not set up an appointment without my mom being there too. They went back and forth on the call for a good 8 minutes before my dad told him she won't be there and if it's a problem then don't come. Is it just a salesman tactic of "convince the wife it desperately needs to be done so she can convince the husband they should do it"?