I would think a better way to solicit donations is to see if you can get a local media outlet (TV, newspaper or radio) to sponsor your trip and do a human interest story on the work you're doing there. Or, at the least, to get them to give you some free ad time.

As for the original post, miles would sway my donation but in the wrong direction. I may be in the minority; I don't want any portion of my philanthropy wasted on giving something to me. I want every dollar to go towards the cause I'm donating to.

That's why, when I open those envelopes asking for money that have a dollar or stamps or somesuch attached, I happily pocket the dollar, use the labels/stamps, and go on my way. If they have enough funds to market by giving away money, they don't need mine.