In a free-market economy, an entrepreneur is entitled to charge what he sees fit for his product. And as with different grades of foam, so too there are different grades of patterns. $50 for a good pattern is in no way out of line. $50 for a lousy pattern will put the pattern maker out of business in a hurry!
Remember that when you buy a pattern you are not merely paying for the paper pattern, photos, instructions, etc., you are also paying for the access to talent, the engineering and the costs of marketing to make said pattern(s) available.
I understand that for some $50 is a drop in the bucket and for others it is a small fortune, but neither situation really speaks to the issue of the quaity of the product. But just because I can't afford a BMW it doesn't mean that they should charge less for them!
Note too that the pattern comes with a piece of reticulated foam which by itself is a $20 value. When you stop to consider all that you get with this offer, its really quite reasonable!