It works in a pinch, but you'll be buying ice every day.

Yes, but you’ll hate it after a week. A decent cooler works fine for a weekend trip. For longer van life, it’s a constant chore. Ice melts fast in a hot van (especially if it’s 90°F outside), so you’re draining water and restocking ice every 24-36 hours. Temperature swings mean dairy and meat are risky by day three. You also lose a ton of space to the ice itself.

The real limitation is convenience. A proper 12V fridge holds steady temp, uses less power than you’d think, and lets you forget about it for a week. A cooler demands daily attention. If you’re just camping for a few days, go for it. If this is your home, spend the money on a fridge. This is not where you save a hundred bucks.