If you were the family facing malaria, and someone tried to donate the nets to you, would you sell them and donate the proceeds to their local soccer club?
What makes me value the former more than the latter is that it is closer to me. My utility for problems near me is much higher than for problems far away.
If my family would face malaria, I would care more about that than about faraway soccer clubs.
Also, I find that goodwill at a distance has a terrible track record. In a recent case, someone who was preaching effective altruism stole 10B instead. I'd rather he stayed poor and donated $10 to the local soccer club.
And certainly no dorky nerds unable to comprehend human reality and attempting to force everyone in their abstract streamlined toy-reality with Philosophy 101 word games will change my mind.
For Malaria, there is not even a debate that it historically was a very widespread disease with high impact in economy and also in warfare. It is estimated that 60000 US soldiers died to Malaria alone in WW II.
I think people should be more modest and realistic, and not dream of solving every global problem. Not making things worse would already be a good start.
2) I use the heuristic that where there are more participants and intermediaries, it is more likely that something ugly will happen even if the original intentions were noble, which is already a big if.
3) I prefer improving my own neighborhood which also affects me, to some abstract global goal which I find less tangible.
EDIT: 4) I am put off by the grandiosity of "saving lives" far away, and I prefer more modest goals, e.g. provide a warm soup for the local soccer team.
I most certainly don't know that. The more local, the more immediate, the less distance between action and effect, the less unintended consequences, the better.