Reason for encryption?

Hi,

I am using this module and it really works well - thanks for creating it.

I noticed on the module page that one of the features is:

encryption of email addresses with

* Invisimail (Drupal 5 + 6)
* SpamSpan (Drupal 6 only)

I checked the HTML of my page that uses the Email Field module, and it seems that the email address is NOT in the HTML.

So I am wondering why the email address would need to be encrypted. Sorry for my lack of understanding.

Thanks for your time and effort.