LOL They've done it so that you can make *any* offer, but because of the starting reference point, you'll offer more than $1-$2 because you've got this idea "OMG IT'S A MILLION". Or, as she mentions in other "make an offer" spaces, she doesn't have an exact value for it, so people should offer as much/little as they want.
I've got coins from her/them, and I was happy with the coin and service.