this was a counter to the "iphone users get them for free, why don't we?" argument rather that the today/yesterday purchase argument.That's not the issue, the issue is for the same product at the same price, if you buy it on Monday it's $20, if you buy it on Tuesday it's included with your purchase. So your example is very flawed and not so much of a given as you seem to imagine.
in terms of the buy today get one thing, buy tomorrow get another:
what seems to be odd here is that if you buy a mac with tiger with iLife '06 14 days (i think it was) before leopard comes out they upgrade to leopard and iLife '08 for free. with apple it's never a generous time period but it is normally there.
but in this case there was no backward allowance at all, which i do find odd.
thinking about this last night i think part of their cock up was in calling this the 1.1.3 update. if they'd said for $20 we're releasing the iPhone apps as an optional "utilities pack" for iPod touch users, and then a couple of months later said "we're now going to make this standard" there would have been less of an outcry.
but ultimately there is always going to be a line where one side of it you get one deal, the other side you get the other deal. that's the price of progress.