It's was like that in high school for me too, except with mainly Mexicans because we were in Arizona. Basically every year people would wear the shirt that knew them and that'd basically be it.
As for supporting the person after they died, I know that a decent amount of money actually went to the family of the person. When you're selling ~$10 shirts for $25+ and 30-40 people are buying it, the family does get enough money to support a funeral for the person. It's not like the profits are enough where they can set up a college fund or whatever you were suggesting.
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