I figure if it's a script, the $300 will disappear instantly. But if it's manual, it's unlikely that someone could manually xfer that at a Starbucks counter w/o getting questioned.
Confirmations (max was $100 at a time):
The card was not hacked. Looks more like you're just trying to promote your link. Thanks though.
So someone either bought exactly $45 worth of Starbucks on the card within minutes of me putting $49 on it, or someone is hacking it.