If you are in finance or health there can be legal reasons. But I think they are just lazy. Legally, those companies are supposed to log every message or email

If you are in finance or health there can be legal reasons. But I think they are just lazy. Legally, those companies are supposed to log every message or email for a specific amount of time. For you, rather than go about putting the systems in place they would rather not deal with it at all. The bandwidth issues though I have no idea. Sounds like someone found the shittiest provider in your area and got a cheap deal, or greased palms.