Tokkemon, you were very quick to judge without actually checking them out.
1. They are not just a printer, they publish new editions as well as new works form living composers.
2. If you don't consider assigning you a free ISMN code (which allows the book to be distributed in stores), advertising you on both SheetMusicX and Amazon websites, and including your work in their catalog that is distributed internationally, then what exactly do you consider promotion?
3. You're not paying to be printed, they are taking care of several costs you don't have to such as: a working website with a payment gateway, promotion of the website, billing and shipping fees (except the shipping rate which is paid by the customer), printing costs (top notch printer, high quality paper, toner, maintenance).
If you'd try to publish with other publishers, here is what will happen:
1. They will deny you because you're not famous and can't generate a minimum of 50k dollars a year.
2. They will deny you claiming that you "don't fit their catalog requirements", one of which is "generating a minimum of 50k dollars a year".
3. They will accept you, if you cover a print run of 3000 copies upon being published.
Try to publish a novel and you'll see how that goes. The publisher will make you pay the print run of a few thousand books, and you're supposed to make them sell, they will just store it and ship it, and you have a start up cost in the few thousand dollars. And you're complaining about a 40$ fee that covers website maintenance, product page display for your book without expiration date (on SheetMusicX and Amazon), printing, handling, shipping to the customer, while you make 1/3 of the sale?