OK, those are good examples. I didn't remember the specific numbers, but now I'm wondering why Ronald had to suffer with a broken wand so long if they are just 7 galleons. Hogwarts seems to be expensive; surely letting Ronnie go without, damaging his grades and learning, isn't a very good idea.
It might be partly psychological. The Weasleys are poor, and they're habituated to trying to save money. Ask someone who lived through the Depression whether they would rent a nice suit for a job interview, or pay double for high-reliability smoke detectors. Or, ask yourself whether you have more than one smoke detector in each room of your house, with the batteries changed out of phase (one set replaced in summer and winter, the other in spring and fall).
ETA: There is now a third thread, so send new comments there.
Since the first thread has exceeded 500 comments, it seems time for a new one, with Eliezer's just-posted Chapter 33 & 34 to kick things off.
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