I just got the notification for the 'You've earned the Making a living achievement!' event, however it's showing on the achievement page as having the 1bil achievement, even though my only shop I've ever had hasn't even reached 500k yet. It's awarded me the Billionaire title as well.
I'm pretty sure if you raise a ticket the admins can remove it if it has been given incorrectly. :)
There is the possibility that your stats carried over from a previous legacy shop.
Oh I did forget about the legacy shops, it's been so long. I did assume though that the new shops would have a separate counter for that, because I'm fairly certain the total on the achievement page has always shown the same number as the info on my current shop page, and I last checked it only about a week ago (and it still read just over 300k)
I was also unsure if this would warrant a ticket since it's not something game breaking (awards only a title rather than a specific item) and seems more like an annoyance.
If you have a question or concern about something specific to your account, it's never a bad idea to file a ticket. The admins can look into your account logs and see if it was awarded in error or not, and if it seems to be a bug that needs more programmer attention they may direct you to make a bug report thread about it.
I understand not wanting to be a bother, but that's part of what they're there for and the staff I've talked to in the past have always seemed happy to help as long as you're also polite about it. :)