*looks left* *looks right* Invest in an adapter? Because there's totally power plug thingies for standard appliances for 12v sockets. Don't even remember them being very expensive. And hey, you're not the one that eventually has to replace the battery... right?
The problem is less them being expensive and more that the ones which plug into a 12v socket just aren't very good. They overheat easily, can only run for short amounts of time, don't provide all that much power (just barely enough to keep a standard laptop charged), and in worse cases can actually kill the 12v socket they are plugged into (this happened to my previous truck).
You want a reliable AC inverter, you have to get one which plugs directly into the batteries using cables. This isn't possible on this particular model of truck without a major project since the battery case is separate from the cabin.