Muse doesn't handle Google OAuth properly (probably)

Issue: I created a muse account a while ago using Google OAuth, and bought some muse sounds. I have since changed the email address associated with that google account, and now logging into Muse with google creates a new account (I can tell because my purchases aren't in my library). This can be fixed by creating another new account with the old email address (however this isn't always possible; you may not be able to access the email address anymore depending on your setup).

However, the massive problem which this implies (but I have not been able to test), is that if someone who has spent money on Muse products releases an email address back into the pool of some email client (e.g. gmail), then a malicious person claims that email address again, they could potentially now have access to those items without paying.