If that is a concern, then you can all ways change the password again, in the
<user control panel> >>Profile> Edit account settings
How ever :
-- to my email address. This is not secure.
If your e-mail service or address is not secure, perhaps you should look for a more secure service. ? There is nothing we can do about that on our end.
I can not understand that websites still do this these days.
Actually that is pretty standard for a forum, some generate a random password, and send that by e-mail, and then the same you can change it after you log in.
As far as "websites" go, most do not have a registration, login option, not to the website it's self, but it is normal procedure to need to register, get a password, and login , to use any forum, or comment area that might be part of that website.
Agreed , it would not be wise to use a insecure e-mail service, to register and receive a activation e-mail. But most people all ready know that, and know to simply change the password that was sent by e-mail. It is also a good idea to change your password every so often, if you are that worried about security.