You can send email using EC2 instances, including mass commercial campaigns (aka "legal spam"...). However, there are a few things to do, more specifically, yo

You can send email using EC2 instances, including mass commercial campaigns (aka "legal spam"...). However, there are a few things to do, more specifically, you must contact AWS to get "clean" IP ranges (fresh IPs, never allocated to instances), sign some agreements and pay additional fees. It's not exactly as simple as an API call to create an ec2 instance, but it's doable. With random IPs, there is a good chance indeed that it is already burnt by a previous allocation.