I just posted in this thread too.  We've tried all the tricks with ZERO results. No idea what the end game is for the account creator, however store owners run a huge risk of having their emails reported as spam to ISP's which will cause deliverabili...

This solution did not work for us.   The fake accounts are still being created.    Do you know how to turn off the Shopify welcome email to new accounts so those emails are not repeatedly reported/marked as spam?