Of course it makes sense; when you stick a price on a new service and find out a couple of years into selling that service that the price you put on it doesn't level with the costs you are making to maintain it. Then you need to level it; moral issues aside (some say the ISPs lured clients in with low prices only to raise them after they were in), that's the way it works. But then again, just raise the price, and do not block certain ports and sell it as a 'mobile internet' subscription or charge extra for 'certain kinds' (e.g. skype, whatsapp) of data usage.