"Data hogs" how you eloquently put it are in fact using what they are paying for, UNLIMITED data. Last time I checked, unlimited means without boundaries, no restrictions or controls. Therefore, it is not the fault of data hogs that they use 2, 3, 5, 10 GB per month and other non-data hogs use let's say, < 1 GB or < 500 Mb per month.
I'm curious as to know what YOUR definition of a data hog is? Keep in mind this will be strictly your opinion, not a fact.
The issue is not the amount of data you are using. It's how you are getting the data (via tethering). Tethering is against AT&T's terms of use for the unlimited data. The fact that they haven't gone after you for it is only luck. They may be more vigilant now that there's an explicit tethering package.