In spite of what some folks think, dodgy boxes are not a form of market correction sending a message to big corporations. They are market destruction and sabotage.
In a functioning market, if Sky, Virgin, Eir, Netflix overcharge or underperform, a legitimate new competitor has the potential to enter, compete on price/service, and win customers. It's not easy but it is possible. Dodgy box operators are not competitors in this sense because they do not have to play by the same rules. They are selling stolen content without the high cost of rights (i.e. paying the workers who created the content), infrastructure, regulation, tax, compliance, and so on, so of course they can undercut legal providers and make them seem expensive.
With hundreds of thousands of people using the boxes, the damage is not trivial. Revenue is pulled out of a productive, legal ecosystem that funds sports, film, TV, journalism, crews, customer support, future programming. Less money made on Premier League or big boxing matches means less money available for women's sports or other areas that are already neglected. Less money means less risk-taking, fewer new commissions, less investment in new talent, more recycled "safe" content, and fewer jobs. This is bad for society and the economy.
On top of that, piracy operations are often linked to wider criminality, so there is a good chance users may be helping to fund organised crime.