i do not know enough context to comment specifically on the supposed stalking issue, but i do know this:
when public figures have to remind people to respect their privacy, may pinanghuhugutan yan. even if veiled as a friendly reminder, there is a reason why they felt the need to say that.
their private lives do not cease to exist because they are public figures. fans play a big part in the success of idols, but it does not give the right to let them be when they need their private time.
a decent fan and human being should understand boundaries - no excuses.