First are you an Avast user ?
I'm not an Avast Team member but an avast user, I would think it unlikely.
Buying email lists would have to come from a legit company and even then most lists are full of dead emails, one off use and they would have to be security interested email address or they really are a waste of time, very unproductive.
If you are an avast user, have you used the hacked email check service (I'm not sure if that is the correct name) as I don't use it and I have never received any unrequested/unexpected emails for avast.
You don't say what the email was about, so it is hard to guess what the reason might have been.
Do you happen to use the