I've yet to see a fixed ISP that doesn't give out email addresses; though I very rarely meet anybody who used them as anything other than a fallback for their webmail addresses.
Mobile carriers even still seem to, though they are optional and require an additional setup step.
I haven't seen ISPs give out emails addresses like that in years (I now my last couple of ISPs have no such thing).
So you're basically limiting yourself to people from universities, or who've had an old-school ISP for a while.