In the US, one of the key things that Prodigy (remember them?), AOL and some other providers had was that they had a lot of "local" phone numbers instead of "long distance". This meant that your connection was a single charge and didn't rack up with time. That was a BIG deal.
In addition, email addresses were still sufficiently uncommon and hard enough to get hold of that people were using "unmentionable" means to get them even up to about 1994 or so.
To get on the actual internet, you had to wardial the telephone exchanges and happen to luck upon an unsecured university dialin server, from which, if you had a printout of IP addresses from a book or BBS, you could telenet to other servers to use gopher, ftp, irc, MUDs, etc. All plain text mode of course.
AOL on the other hand was a lot more user friendly and lively, just dialin with a graphical interface and tons of groups, chat channels, games, etc. just right there.
It wasn't until the internet was finally opened up to the public in the late 90s that AOL added an abstraction layer over the internet. Even then, it likely had all types of modem available, where, for instance, I tried IBM's ISP but it used modems that were incompatible with the modem that came installed in my IBM PC.
Instead of this bot driven email, I made use of the alt.binary.mac.applications and similar newsgroups.
But this email system you describe sounds exactly AOLish version of newsgroups. A way of holding someone's hand while the powerusers just went straight to the source.