It's a vicious circle, though. Apparently the "justification" for the hyper-inflation of software prices is the impact of piracy. The irony here being that the increased prices mean less people can afford to buy the games and thus pirate them instead.
It's the same in every field where things can be copied, and DRM doesn't matter.
There's no way to get round it, sadly. My slightly naive options would be to either seriously drop the prices and hope for the best or offer other incentives to buy, much like Kickstarter offers pledge rewards (such as help and support and access to a special bonus thing, like resources or a web site) that would appeal to the target audience.
I'll be honest, I have downloaded games, but purely because I don't want to spend £40 on a game that might be rubbish or that I'll play for 20 minutes and get bored of. If I play a game and like it enough to come back to it, then I'll bin my downloaded copy and buy it. The sad truth is that there are more people out there who would just say "meh, I've got the game, I'm happy and not hurting anyone" then look at homeless game developers in the street and get annoyed that they haven't got jobs.
The mediums are there now for game developers to engage the enthusiasm of their potential audiences now, with game footage, interactive content, marketing and so on - things like remote distribution work quite well (if only the game sizes would come down a bit). Most technical solutions to these problems are dealt with by crackers in a matter of hours these days, so more creative ways need to be found to generate cash.
I believe Microsoft took a quite creative line with piracy. They were rumoured to state that the reason they rarely crack down on piracy is that it means copies of Windows are being used, increasing their market exposure and value. Rumours have it that they INCLUDE pirated copies in their stats of "copies of Windows in use". Even if it's untrue, it's still a great idea, as long as there's been enough profit to cover the costs and wages for the developers. Anyone who sees a pirate copy or plays one has a chance to become a buyer, after all.