In France, on of the biggest journals, Le Monde, is also a hassle to unsubscribe. Subscribing is very easy, just enter credit card online. But for unsubscribing, you have to send a registered letter with recorded delivery. This is a hassle, you have to go to the post station, and is also pretty expensive (around 5-10 euros), which is almost the price for 1 month subscription to the journal. I find this unbelievable that you can't unsubscribe online (even for the online edition).