Had that happen a couple years ago at a CG in east Texas. A neighbor had their toad's fuel filler door torn off and their tank punched on their "A". Ironically, my truck had three full five gallon gas cans in the bed (tied down with bungee cables) for my generator, and was untouched.
I wouldn't say thieves are smart. It is not uncommon to read about some meth-heads trying to cut down a live electric wire, only to get zapped, or find out that the wire is aluminum or CCA. A couple years back, I had the "output" of my bag toilet stolen in a heist where a truck pulled next to mine at a truck stop (I was inside buying a drink), a guy jumped from truck bed to truck bed, grabbed my garbage, then took off going the wrong way on the highway. The attendant offered to call the sheriff, but for $0 loss, why even bother.