that's actually a good question and one I asked when I was looking for my acoustic...
the answer is yes.. cost does make a difference with acoutics... the more you pay (in most cases) gets you better wood, solid neck and headstocks.. better sound boards and just in general, a better guitar. Don't think it's true? Go to any GOOD guitar store that has a separate acoustic room and try a few.. pick up the $99 blue light special and then grab what you would if you had a wad o' dough to spend.
Lastly, I would never buy a guitar that I hadn't played first. In another post I had asked a question and one of the replys made a great deal of sense to me.
All acoustic guitars seem to have their own kind of "personality" some are good strummers, some are good finger pickers.. some are jacks of all trades..

If it's just so you can have something to play on, $99 is cool, if you wanna play it for a long time, spend some time looking (and not just at the price tags) there are plenty of good guitars out there that won't break the bank.