Providing tools for small-businesses ultimately means you're providing easy-access to people with few barriers I think places like MailChimp are pretty easy to

Providing tools for small-businesses ultimately means you're providing easy-access to people with few barriers I think places like MailChimp are pretty easy to abuse for that reason. Compare that to an enterprise service provider where I need to commit to tons of upfront money in order to access the service and I need to manage my own reputation of my sending domain.