While it may be more "proper" form (depending on how you like to do things) to edit a user crontab or simply add a script to one of the /etc/cron.hourly||daily||weekly||monthly directories, I don't see what that has to do with his problem.
I would have been more explicit, but my question was not about the correct usage of crontabs, but I was wondering why "crontab -e" edit the system crontab and not a per-user basis crontab (which is the default behaviour). I was thinking about some mis-configured configuration file. Next time I'll be more clear. Sorry.