I'd be a little torn on this. On the one hand, I've seen someone land first hand expecting fuel, only to find there isn't, and they don't have enough to get to the next nearest airport and the desperation that causes.
On the other hand, that seems like a planning problem. Didn't verify fuel available at their stop. Didn't have enough reserve to make it anywhere else. If the airport doesn't have fuel, that leaves you now in the bind without fuel in your plane, so just shifted the problem.
Not to mention, you have no idea about the fuel in the "donor" plane. Is it Avgas or Mogas, or something in between? Was it checked for ethanol? How old is it, did you just siphon out of a ramp queen?
And as the owner of the "donor" (ok I laughed a little after typing that
), the idea that someone was dinking around with my airplane without my knowledge or consent just sets wrong with me. It would be one thing if I was there, and offered to pass some gas to them. That is what I've seen happen before many years ago when based at an airport without fuel on the field. A guy doing a XC delivery of a Pitts landed low on gas, only to find the fuel farm hadn't been delivered yet to the new airport. He was on fumes, because well its a Pitts. Some guys that were on the field washing their plane were nice enough to sump a few gallons out of their plane to get him over to the next field.