The user base might be really huge. So, solutions such as google apps are not financially viable. Hosting your own server might be a pain. Please share any experience (exactly how painful is that). Both cloud based and server based are options and something really cost effective is desired.
There are many companies doing this for bulk email sending like sendgrid, mailjet, mailchimp etc. but no one is doing it for hosting emails with bulk pricing.
i don't know what rates you consider reasonable, but there are plenty of services that do it. rackspace and fastmail are two off the top of my head. I consider them far too expensive for myself though.
exactly, thats just too costly. I mean it should really not be this expensive. Why email hosting is being charged per mailbox I do not understand. The maintenance is not per mailbox. Its per mail server and hence should be the costing.