How should I picture "Hitchhiker" - in the book, isn't the main character an unintentional observer/participant? So is this a beginner?
Or perhaps a hitchhiker is a hardened, obstinate person who enjoys the frontier and moving around a lot?
I don't know; it never made sense to me.
I have always interpreted such titles to be a reference to this in-universe guide rather then to the novel or its characters.
We could split hairs over the fact the in-universe guide is more analogous to Wikipedia in scope and scale than a more condensed tutorial or primer, or whether the reference is obscure enough that it confuses, alienates, or distracts readers who aren't part of the intersection of Hackernews Readers and Hitchikers Guide fans.
It never really bothered me but I was a huge fan of the series when I was younger.
Edit to add: as I am a technical writer on the side, it's a timely reminder to avoid any analogies or cultural references that require knowledge others in my target audience might not share. So, interesting point!
That's the original inspiration for the in-universe Hitch-hiker's Guide to the Galaxy and perhaps the better point of comparison for other guides that are named after it.
[0] https://en.wikipedia.org/wiki/Hitch-hiker's_Guide_to_Europe
I read some excerpts here https://h2g2.com/edited_entry/A4158164 and it definitely adds context that only really improves my interpretation of the Douglas Adams series.
"Always carry a towel" is one such reference that I can now replay and re-imagine as a parody of the original guide. I'd assumed them to just be a random amalgamation that parodies the overall genre of various guides and travel literature, it's fun to know there's a solid reference point.
As for the relevance of the "Hitchhiker's Guide to <subject>" title format in light of this information, I agree with you that the original source is a better comparison point; while there will be a lot of fans of the Adams work who can relate on that level, there will be others who either owned or knew about the original source of the parody who will interpret the format more closely to its intention. And ultimately it's a format that's so frequently used that there will be a broader spectrum of people for whom "Hitchiker's Guide..." is just synonymous with "down and dirty advice to get you started quickly, without pretension."
This has turned out to be an interesting rabbit hole, personally at least.