Stop notifications from cron job

This is actually a continuation from another ticket thread (User Having Trouble With Registration - #261634), which you helped me with. The code you provided to set up the cron job was successful:

/usr/bin/wget -O /dev/null "http://yoursite.com/index.php?option=com_easysocial&cron=1";

However, what can we add to the code to prevent from receiving the email notifications? When we contacted Siteground support, they said to simply delete the cronjob, but that didn't seem to be the right answer, as I assume that would have stopped the email processing.