Market for dual voltage is bigger than you think
Marine isn't the only market for 'em...RVs and 18 wheelers that have sleepers also use dual voltage refrigerators. If you go to the Norcold site, you'll see that marine and RV refrigertors are the same ones...even fit the same cutouts. Although the storage boxes are designed differently for use in RVs, trucks and powerboats than for use on sailboats, the compressors, motors etc are the same no matter how the storage box is configured.Granted, there ARE a lot more uses for AC only than there are for dual voltage. However, because dual voltage fridges actually are running on 12v power all the time, whether they're connected to 115v/ac or not--an inverter converts ac to dc when connected to ac power--that does account for at least some of the difference in cost between dual voltage and ac only.IMO, the best choice for single voltage is DC only, not AC only. While away from the dock, your battery keeps it cold...while at the dock, it's still running off the battery, but shore power connected to a battery charger keeps the battery charged. Coleman even makes portable DC-only units that can be plugged into a "cigarette lighter" receptacle...about $60 at Sams or Costco.