Maybe donating for Malaria would just have been to silence Cueball's conscience, and Megan's comment made him realize that he really wanted to spend all the money on games. It could also be that Megan's snide denigration of Cueball's act of charity as inadequate and self-serving has dissuaded him from any act of charity at all, if this is what it gets him. In any case, it seemed to give the opposite effect than intended.
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Supposedly these kinds of conversations happen to Randall on the internet, so a good way to avoid them would be to quit participating in stupid and meaningless discussions there. Trolls are adding improper contributions at forums to annoy other people as you can see here: Internet Argument Techniques.
- Cueball: I'm going to buy this $10 game I want, and I'm donating $10 for malaria eradication.
- Megan: If you actually cared, you'd skip the game and donate all $20.
- Megan: What's more important? Games, or mosquito nets and medicine for kids?
- Cueball: I think I'm going to buy these two $10 games I want.
- Friend: Cool; which ones?