Apple, Google, and Valve are creators, and they're also providing the service of being middlemen for you. They deal with hosting, serving, taking payments, so on and so forth. There are AAA companies that have found Steam so much better for distribution that they no longer sell any other way (look at Paradox Studios, for example).
And while you're locked into Apple (not that anyone is forcing you - and Apple basically created that whole industry), with Google and Valve, you're free to run your own setup and deal with all the middleman stuff yourself. 30% to hop onto their infrastructure and let them deal with bad payments is a pretty good deal.
In short, you can always tell the people inexperienced in business in these conversations, because they think that 30% is a crushing 'take'. 30% is actually pretty damn good - normally in retail it's what you'd get, rather than what they'd take.
And while you're locked into Apple (not that anyone is forcing you - and Apple basically created that whole industry), with Google and Valve, you're free to run your own setup and deal with all the middleman stuff yourself. 30% to hop onto their infrastructure and let them deal with bad payments is a pretty good deal.
In short, you can always tell the people inexperienced in business in these conversations, because they think that 30% is a crushing 'take'. 30% is actually pretty damn good - normally in retail it's what you'd get, rather than what they'd take.