I used MEGA for a while and was pretty happy because their free plan is (or was back then) very generous, and they had a BSD command line client. Out of the blue, my account got blocked, and when I logged in, something along these lines appeared on the screen:

'You are using the same password for MEGA and other services. This is a security risk and is not allowed'.

That's one of the shadiest fucking things a cloud company could write. First, not true, second, even if that were true, how would you know it.