It isn't odd not to see smoke except when they are firing their burn-down
pit.
Many Southern barbecues, especially in the Carolinas, cook over burned down
wood charcoal. As such it doesn't give off much smoke. Wood is burned down
to hot charcoal and then it is added to the pit. Often there is no indirect
element but rather the fuel is directly under the meat, with the fire pit
distant enough to keep from burning the meat but at the same time creating a
nice bark. Given the lack of smoke flavor, if you don't get some nice brown
bark or skin in your pork, it tends to be very bland. You may just get
greyish-white internal meat as shown in the posted pix which IMO has little
flavor other than a vinegar based sauce.
If I were cooking in that style I think I'd bone and butterfly butts or
shoulders and season well so as to maximize the amount of exposed surface,
and therefore bark formation. I often do this anyway even in a smoky pit.
Some flavor around the bone is lost but the crusty, flavorful, salty bark
more than makes up for it.
MartyB