I went to sign up at a couple of sites today that insisted that I use a G Mail email address. They actually wouldn't let me sign up if I didn't. What is the deal with that? It seems downright stupid.
First off, every other TE, mailer etc. manages to successfully send me email to my regular account. So why try to insist that this email address is not acceptable? It's just rude.
Second, I only use G Mail as a junk email account. So will read the sign-up email to click the link to verify the account, but that is the last email that I will ever read from your program. So if your goal was to make sure I never read another email from you for the rest of my life, well done - mission accomplished.