I am genuinely interested in knowing the appeal programmers find in fonts.
When you consider that programmers spend most of their time reading code, it's not surprising that many programmers care about the font being used.
Monospaced fonts are also interesting from an artistic perspective that resonates with programmers. Font designers are able to be expressive and original despite — or perhaps because of — the constraints of the problem: all characters must have the same width and the text should be readable for long periods of time, often at small sizes.