You are just ruining your own service by doing that, driving away your users by making their experience miserable.

Your mail-app for Android was flooding with Ads which even forced me to click on them by accident because they were suddenly popping in between my Emails, looking like unread ones - so I uninstalled your app to never use it ever again.

I will do just the same with your email-service and swap to one of the many other providers out there - if you intentionally make my user experience miserable, just for a few bucks more in your pocket, you simply lose me as a user - and I guarantee you that I won't be the only one.