Using .htaccess in Cpanel to block domains that pirate images

In simpler times I dealt with image pirates by substituting a jpg image of my copyright violation warning for the pirated image and replacing it with a renamed original image in the html code for the affected page. Once I substituted a picture of a roasted caterpillar that I found in a nut; it's still on the offending site. There are too many such images nowadays, so I have tried to edit my .htaccess file in cpanel, to which I can add new lines, one for each offending domain, whenever I check the "recent visitors" file in cpanel.

I attempted to make use of the instructions posted here:
http://www.whoishostingthis.com/blog/2011/03/04/hotlink-protection-cpanel/

Here's a truncated version of my .htaccess file, with sensitive information taken out:

|RewriteEngine on
|StuffThatWorks
|order allow,deny
|allow from all
|/StuffThatWorks
|
|RewriteCond %{HTTP_REFERER} !^http://(www\.)mydomain01\.com/ [NC]
|RewriteCond %{HTTP_REFERER} !^http://(www\.)MyDomain02\.com/ [NC]
|RewriteCond %{HTTP_REFERER} ^http://(www\.)blockeddomain01\.info/ [NC,OR]
|RewriteCond %{HTTP_REFERER} ^http://(www\.)blockeddomain02\.org/ [NC]
|RewriteCond %{HTTP_REFERER} !^$
|RewriteRule \.(jpeg|jpg|htm|html)$ - [F]
|deny from IP.address0001
|deny from IP.address0002
|...
|deny from IP.address1567

So far, my changes (everything but the long list of "deny from IP.address####") have had no effect at all. Is that because my syntax is wrong, or is it because the offenders are using redirects, etc. ?