Your wife is nuts. I consumed eighteen Endurolytes and seven eDiscs on yesterday's 200k Permanent, plus three packets of HEED and one Perpetuem. Salt/electrolytes are critical for endurance riding.
I don't think the soda pop is a good idea though, since the carbonation fills your stomach and leaves less room for water and such, but everyone is different. If it works fine for you, keep doing it.