Maybe a better idea for them would be to say charge you $10 upfront for 12.5k email credits which should last you a while. Seems like a better deal for "hobbyists" vs a bill at the end of a couple of months. For MG, they can collect payment upfront. I guess maybe for some people, going from free to $10 might be too much of a leap? We were on the "free" Mandrill plan which became PAID (which we were fine paying) but you have to pay for Mailchimp before you get the privilege to pay for Mandrill (we don't use Mailchimp at all), all our stuff is transactional. Hard to get out of it as we are using both inbound and outbound