I'm glad I get mine free. I'd have well over $200 invested in boxes.
I'd rather put my money into the contents.
Another advantage, but it will influence the kind of wine you drink --
sometimes you might prefer a different size. I have some 5 liter boxes.
They are great for things I use up a little faster.
Also, if you don't drink wine, some juices (unfortunately, none of the
ones I like) are available in these boxes.