It’s rude. Your use of this software forces me to sign up for a Ponzi scheme in order to be able to reach you. Most of us use anti-spam software which isn’t so intrusive.
It also doesn’t work. I have been required to verify my identity there many times now, even though it’s only supposed to happen once. And it isn’t secure, since forging return addresses is trivial.
(What is SpamArrest? It forces everyone who sends the recipient mail to go to the SpamArrest site to fill out a capcha).