How To Include Signature In Reply Gmails

I thought one way of publicizing my book would be to include the link to the product in my signature in my gmails.  I was very excited to set it up.  First I went to settings:



And set up my signature...

Upon completion, I was ready to fire it up!  However, they weren't appearing in my replies!  It was only showing up in new emails I created.  I tried copy and pasting my signature into my email, but that wasn't going to do.  That's when I learned in order to include them in replies, you need to go to the LABS tab and enable it there.





Why google put it here and not in the settings, I have no idea.  It seems counter intuitive, especially for an Outlook user myself.  But now you know.