Am I wrong to assume that people run WordPress sites (and possibly even large ones) without "transactional email" services from "Mailgun", "Mandrill", "Sendgrid" etc. ?
There seems to be information describing what these services do but not necessarily describing its importance and necessity which leads me to believe that they are NOT that necessary.
Lets say a website visitor signs up to a BuddyPress site as a new member, what shoots off the various emails such as "confirmation", "admin notification" etc. ?
Would all these emails not be sent out just fine without any further outdated SMTP plugin from wordpress repository ?
Is it that some shared hosting servers cannot send large amounts of emails and this causes emails to not be received etc. ?
I can understand/accept this for auto sending large amounts of emails in a BuddyPress site, but this is also important for receiving email via an online form ? I have read these transactional services are way better at blocking spam than any wordpress spam plugin.
And finally how does these services affect a multisite ?
If paying for such a services, every email transaction though the multisite network would be taken into consideration (billed)
Any kind thoughts/assistance in this would be greatly appreciated.