That's why it should be optional, not global. Taking the Gazza thread again, had anyone quoted me in that yesterday, would I go trawling through all of them pages to find it, would I hell. But, if I was interested in comments made quoting my post then it would be quick and easy to find.
I turned off the "like post" alert on the other forum, also the alerts for when a new post was added to a thread I contributed to, I found that cut down the alerts by 90%.