I know, I heard that even without buying pony merch, you still need to buy food for BronyCon, so in all the thing would probably cost around $1,500 by plane, $1,300 by car. Both include a guest pass ($75) or sponsor pass ($125), Food (around $200 based on the restaurants around the con), Merch (depends on what you buy, normally 200 bucks), Gas for car rides ($180 or less), Plane tickets for the plane ($200) and a lot of other things, like paying for tolls, paying for hotel rooms.. etc.
My parents would never spend 1,300 bucks on a convention.