Anybody who's done much book-shopping in Mexico has probably noticed that the relationship between the text on the spine and the cover is the opposite of what it is in the US: if you have a book standing up with the cover to the right and the spine facing toward you, in Mexico the title usually reads from bottom to top, while in the US, it reads from top to bottom. In other words, you tilt your head to the left to read the title of books lined up along a shelf in Mexico, but to the right in the US. When you jump between countries but stick to each nation's respective language in your shopping, this is not a huge issue; one can quickly adjust his tendencies, browse the shelves, and find the desired book without any danger to life or limb.
However, disturbing problems do in fact emerge when one is searching for Spanish books at American bookstores, because they carry books both from Mexican and American publishers, with the latter group maintaining the same spine-to-cover typographical relationship in their Spanish divisions that they do in their English arms. The result is chaos, with mismatched spines standing back-to-back. This unfortunate circumstance forces the shopper to bob the head back and forth with an unsettling, dizzying rapidity, which makes the peruser appear to an outside observer as though he were honing his defensive tactics for an upcoming boxing match. Continuing with the pugilistic metaphor, a 30-minute visit to Barnes and Noble essentially bludgeons the brain much the way another boxer might in four rounds of combat, provided that your previous defensive training drills were fruitless. You the leave the store feeling battered. I hereby call for Congressional intervention; no Spanish-reading book-buyer should be forced to suffer this fate.