It really depends on the edge finish you ask for. If you have the shop polish the edges or get a curve edge polish, it can cost as much as you say.
Now if you just get the oval piece cut with the "Seamed" edge, then it can cost as little as $35 for 1/4" (depends on your size). Of course a "seamed" edge is just the sharp edge when cut (sometimes they will lightly sand the edges a bit to make sure you don't cut yourself). If you are handy and don't mind the extra labor, you could sand the edges down to almost a polish with several grids of sand paper and a buffer. It works just fine but won't look as perfect as the glass shop.