Has anyone bought an extra freezer for their rig?

For efficiency I'd be looking for a chest type freezer though that style is not very convenient to use.

There are 12V portable coolers which can freeze. For them the issue becomes battery power to run them plus the other 12V needs. The good thing is that they do not need to be on 24/7. Most are chest type. Go in, get what you need for a few days & get out.

If you have space you can't beat a nice big 4 door fridge. Got one. Can't imagine doing long trips without it. No grocery store stops every few days.