I wouldn't worry about it ?
Because when you get 100's of Bounced e-mails you start thinking should i delete there accounts? Should i ask them to update there e-mails?
At the end of the day IMO its House keeping you can do with out.
And it only costs you time.
Ive not sent e-mails out for years either.
I used to do it as a News letter and a obligation to sponsors.
I do wish that we could turn off 'receive notifications' without having to login to someones account.
I dont get that ?