Ask HN: Affordable options for maintaining promotional email lists?

I write articles online and let readers subscribe to an email newsletter if they want to keep up with new posts. I use Mailchimp which works well and handles the subscription form, double opt-in flow, and provides a nice UI for composing emails quickly. No complaints about the product.

The problem is that the pricing model seems aimed at a different kind of market. Once you get over 5k subscribers, the prices go up very fast. They charge an extra $5/month for every 200(!) additional people on the list. For my use case, that seems like highway robbery for the incremental service provided. My bill goes up nearly every week for running a very simple (and not terribly large) mailing list where I send at most a few emails a month.

Does anyone else have experience using other mailing list providers that are aimed at a consumer who doesn't want to pay thousands a year to maintain a simple email list? Any recommendations?

I'd prefer not to build my own system using Sendgrid/Mailgun/etc for this simple use case. I don't need to send any automated/transactional emails.