OK, as far as your ISP doing that, I would be changing supplier if mine did it.
However regarding spam or as jazzmandan found, downright vicious malware attacks from E Mails, and all because the E Mail purported it came from FedEx.
As a warning to everyone else even if expecting a parcel, think carefully about the so called E Mail sender, have you at any time given that organisation your E Mail address?
Obviously, if you haven't done so, then it can't possibly be them that sent the E Mail, so delete the darned thing!
If they have never been given your E Mail address, how did they send an E Mail to you is the question to ask yourself, and do take it from me, reputable organisations such as FedEx will not, and do not, go searching all the data bases just to find out if you do have an E Mail address.
That applies to most other companies including the banks.

I have lost count of the number of E Mails I have received telling me there is something wrong, or my account is soon to be closed, and please click this link to confirm your details etc. Most from banks I don't even have accounts with, as well as my own bank. All were phishing attempts or spam, as no bank has ever been given my E Mail address, and never will be.