Dish is a wireless service and so is a cell phone. You can take your cell phone anywhere you go and you can activate additional phones on the account for a small additional monthly fee. The cell phone companies don't care who have the additional phone.
Just a few points I thought should be brought up for this topic:
1. DISH isn't a cell phone company... so that comparison isn't valid.
2. Account Stacking is about what DISH wants, not what you want. If it was about what you wanted, you'd be providing Service to DISH and DISH would be paying you, not the other way around. It's that whole buyer-seller silly thing.
3. It is illegal because it is criminally considered theft and fraud if that's the way Chuck plays it. That language isn't used under residential agreements however because it reads in a very hostile way. DISH tends to only pursue long-term stackers, frequent offenders or commercial stackers. Some do time, some pay fines; the case law can be google'd.
4. DISH charges two full account prices, because it can. You need to remember that every dollar Charlie saves keeps that "America's lowest price" going for one more year. Do you really think he'll discount a second account because you disapprove of having to pay for it? Similarly, do you think he'll let you have free service and get off scott free if you do it long enough?
Will you end up sharing a cell with Bubba if you do this? Probably not. But do NOT put it past Charlie to take you for every cent you're worth if you get caught. He can, and has done so in the past.