Honestly miners only include fees to "support" Bitcoin not out of any economic value.
Now that does _not_ make sense at all.
Of course they support it for an economic value.
Without getting people to adopt the bitcoin currency the economic value of the miners BTC would be worth squat. If you told users hey you all have to process your transactions for yourselves while we [the miners] rake in the dough for producing coins I don't see a widespread case for BTC.
Of course there's an economic motive behind processing transactions for "almost free" right now. View it as a promotional offer to get people hooked on BTC and allow miners and hoarders to benefit from their coin mining, because a currency needs an economy. I have no doubt that transaction fees need to increase over the coming years but if all miners exclude transactions now (if one's doing it, then why no all?) you'll be sitting in your sandbox alone pretty soon without kids to play with. So play nice.
