Don't forget DRM is a product. People make anti-piracy measures and sell them. So they have an incentive to make you, the developer, fear piracy, so that you'll want to use their DRM or use them as a publisher (and they'll provide the DRM). And of course, in return, they take a cut. They don't make games, they get involved in the process of selling your game and in return you let them get some of the profits. They have to convince you the developer that this is a good idea, or you might just sell to teh customer directly, god forbid, and then they get nothing.
This was an easy argument to make to developers when publishers and such also provided so many other things - the printing of physical media, paper manual, case, cd, artwork, extra goodies, shelf space, distribution, shipping, returns, customer service.
But now, w/digital distribution, DRM is often one of the *only* things they have to offer to a developer anymore. So they better get you scared so that you *want* their DRM. Otherwise you the developer might realize you can just deal w/the customer directly w/out need for physical media or its distribution and that you don't need them anymore, and you especially don't need them taking a cut of your profits for doing so little. You might get uppity and try to give them a smaller and smaller piece of the pie.
What they should be offering is exposure. I've some times heard of games for the first time through steam. That's a valuable thing to offer developers. I bet many of these indy games now being sold on steam are being bought by people who never would have heard of said games if not for steam. DRM might be a stupid reason to use steam, as a developer, but exposure is valuable and a great reason to pick a publisher. Its not worth giving a cut of your profits for the DRM, but it might be for the exposure, if they can truly offer it.
fear can sell though. A false dichotomy is implied - trying to make you believe that you either will self publish and lose everything to pirates, or that your only alternative is to use the publisher and their DRM (for a price) and make oodles of money all thanks to them.
Heck, if I sold DRM, i'd secretly encourage piracy as much as i could so that people felt teh need to buy my product all the more. I'd certainly skew statistics to make piracy look as bad as possible, and jump to illogical unfounded conclusions whenever they favored me and fostered fear, though i'd try not to be too obvious about it. I might even start up seemingly independent organizations/websites and have them support my outrageous claims, lending them credibility. I'd assuredly encourage others to adopt false cause & effect ideas in my favor - such as the notion that 1 million download connections of an illegal copy of your game represents 1 million different people (not say 500 thousand who downloaded part then reconnected later to download the rest, or downloads from china from people who could buy an illegal copy of your game on a street corner anyways w/government sanction, or the bots i made as a drm seller to repeatedly download the game inflate the #'s, or little kids whose parents wouldn't have bought the game for them anyways). All to help create the climate of fear i need so everyone will buy my snake oil. Snake oil salesmen are as old as money. DRM is just one of the modern day snake oils.
Not to say there isn't real piracy. But the fact there is real piracy, creates the kernal of truth from which a climate of fear can be created making everyone feel as if they need the DRM (for a cost of course).
So says Smeg