
OK, but the explanation will be disappointing.
1st, to correct an error, it's Yakima, Wa. It is a real, out-of-the-way, non-descript, small place, in the north West, USA. These facts, plus the way the name sounds when spoken, make it ideal for the humor. No other significance.
2nd, "everyone" has experienced the "lost sock" syndrome. You know, doing the laundry, a whole bunch of complete pairs of socks, but, when the laundry is ready to be put away, invariably, a couple of socks have no mates! Where'd they go???

The story line is that they end up in a giant warehouse in Yakima, Wa.

Say it.. Ya..keh..ma.. Emphasis on 1st syllable. It's not my story, but, is of some familiarity here in the US. OK, perhaps reasonably obscure.
So, says I, if socks can end up in Yakima, why not the lost pages??? Boo!!!
And that is that.