There is no point in ever useing charcoal. To grill you are better off with propane, BBQ and smoking requires wood.
The reason I use propane to grill is because it is easy, clean, and efficient. I don't have to spend much time preparing and tamping a wood fire for what is going to be at best a half hour cook. With propane I can have a meal prepared in under an hour from start to finish. The only charcoal that I could do that with is the ?easy light bricks? stuff which is treated with chemicals that imparts an undesirable taste on the food and is more expensive then propane. So I get worse taste for more cost. The untreated charcoal is okay and does help the flavor of the food, but to use properly takes almost as much time as using wood and adds no where near the distinct flavor that the different woods can. And remember the quicker the cook, the less important what you cook with is. For quick grilling, propane wins in my book.
Smoking and BBQ is a different story altogether. When I am going to do either I am already dedicating either a full day to cooking (BBQ) or several days (smoking) so I might as well take the time to set up a proper wood burning pit. For either of these charcoal will not do because I am going to be cooking my meat for a long period of time, and that means they will get the benefit of having that real wood flavor. Wood is in most cases not more expensive then non-treated charcoal (there are some types of wood that can be really expensive to cook with, but you shouldn?t be using those woods unless you really know what you are doing) and wood definitely imparts a better flavor, and it only takes about a half hour extra prep time. What is thirty minutes when I am already dedicating at least 20 or so hours to cooking?