As for a definition of a "Slob Hunter". Well slob is derived from the word sloven for which one text book definition is: \Slov"en\, n. [D. slaf careless, negligent.
For me its someone that doesn't give a d@#*. Someone who is reckless, careless and negligent. What they don't dive a d@#$ about may vary. It could be safety related, ethics related or the fact that they can't hit a barn door at 50 yards yet do nothing to attempt to improve that situation. It could be people who often take shots at ranges that they have never practiced from. Or as described in that article it could just be people who take shots from ranges that are just too far period regardless of skill level. A man that continously shoots at a deer from a range that often takes him 20 or more shots to score a hit doesn't give a d@#* about the animals he is hunting. Doesn't care if wounds them and loses them; doesn't care if he blows a hole through and ruins both back hams; doesn't care if he condemns the animal to a slow horrible death from infection or even starvation depending on the nature of the injury. To me that labels him SLOB.