I once had this happen to me, in the form of a direct request for miles from a "friend of a friend" that I barely knew personally. The problem is that many people don't realize how emotionally attached some of us become to our miles . Seriously, I find that I value them at least as much as an equivalent to cash at $0.02/mile, so I interpret a request for a 25,000 mile domestic award to be a request for $500 cash. If I'd give the cash to the person asking for the miles, then I'd give the miles. Of course, most of these people would never ask for cash, but their view of miles is as something we get for free, as opposed to something we earn.

I'm much more generous when it comes to people that travel with me, as I get at least as much enjoyment from it as the person I bring along, especially when I get to introduce someone to premium international travel that otherwise may not have the chance to experience it.