You Don't Delete Friends Emails Before Forwarding

Whenever we get an email whether directly from a friend or forwarded to us there are a number of email addresses in the email.  When you forward the email you are also forwarding everyone's email addresses which can be "fished".  Most of the time it doesn't pose a problem but I wonder why we all get so many unsolicited junk mail in our inbox.  Why take a chance that it may harm your friends?
When forwarding please address "TO." to your own email address, and forward to multiple others via "Bcc."  Also remove all email addresses from material being forwarded.  Thank You.