^ Bearing in mind that my observations are those of an outsider, it makes sense to conclude that the target market for a tech manual isn't remotely the same as that for a cute, lighter weight offering. The people who might buy Kirk's Guide and other such books are probably the same people who buy Trek gag cards from Hallmark, or the plushy Gorn dolls, or the T-shirts that read "Klingons do it with Honor!"
All of that stuff sells, and it sells by the truckload, and a good chunk of it is likely purchased by casual fans who don't get wrapped up in all of this like most of us do, or friends or relatives of fans who think it's funny or cute and it makes an unusual gift. At one point (don't know if this is still true), the most popular book being sold at Star Trek: The Experience wasn't a novel, or a companion, or a script book. It was The Ferengi Rules of Acquisition, the little dinky book that sat next to the cash register. People passing through the shops and looking for quick gifts for Trek fans back home were apparently lapping that thing up like chocolate flavored Viagra.
In other words, Kirk's Guide/etc = apples; Companion/Tech Manual = oranges.
From where I sit, anyway.