Do you honestly think that spammers cant write a
little bit more code that will parse out the URL
and then parse the email addresses out of web page?
Do you honestly think that most spammers are using custom tools to extract
e-mail addresses from web pages? (There are winblows GUI tools designed
explicitly for this purpose -- you can download them from tucows.)
It would probably help them because they'd have an
up-to-date list of people to spam.
Most places already have a contact list published on the web.
There are also ways of "hiding" e-mail addresses in web forms to make them
harder for spammers' tools to parse, i.e., adam [at] flounder.net, etc.
--Adam