"...or I'll go ape shit on your ass!" The best southern insults are the ones shrouded in subtlety like "I just love how you don't care what people think" and the "Bless your/his/her heart".
Then again, there are some pretty good obvious ones too like "His face reminds me of a drunk raccoon near an exposed septic tank".
Also. The price of those loaves is RIDICULOUS. Do the math.