The following 3 questions:
Were all closed as duplicates of:
Now I'm not necessarily saying that those questions shouldn't have been closed, just that they were not duplicates. Roaming is not the same as data roaming - it also refers to calls.
General StackExchange policy on duplicates is described in a StackExchange blog post: http://blog.stackoverflow.com/2010/11/dr-strangedupe-or-how-i-learned-to-stop-worrying-and-love-duplication/:
One thing I want to be clear about, though, is that duplication is not necessarily bad. Quite the contrary — some duplication is desirable. There’s often benefit to having multiple subtle variants of a question around, as people tend to ask and search using completely different words, and the better our coverage, the better odds people can find the answer they’re looking for. And isn’t that, really, the whole point of this exercise?