I would consider that the main risk of placing the email address there is that in case it is lost, it would be a phishing target for unlocking the device.
This is quite common with Apple devices: iPhone is lost/stolen, and thus the owner locks access to the phone, so it's no longer possible to use this device (unless accessing the Apple account of the owner). However, the message shown for those that find it often includes the email address associated to the account. Thus, what attackers do (actually there are people selling this 'service') is to send a phishing email there claiming to come from Apple and stating that the iPhone has been found, that actually leads to a phishing page from which the credentials of such accounts are harvested for freeing the device.
I find that the same approach would equally work with an Android phone. If the email address shown is the Google account linked to the device (as it'd be usual to be), phishing the account credentials would allow unlocking the device.
Using a secondary email address exclusively for that (which should then receive 0 mails, and you may not even look at until you lose your phone), and not linked to the phone, should help.† Although you should be very wary that anything received there should be presumed to be a phishing attempt (note that any notification regarding the lost phone would not be sent there, only a human that had read the message would direct phone-related mails there!).
† Of course, store the name and password for that email safely, as well as of the primary account where the device backups everything.