Alternate racial traits aren't traits
Alternate racial traits such as those listed in the descriptions of half-orcs and humans (for example, acute darkvision and adoptive parentage, respectively) are specific and unique to those races and different from the traits the GM usually allows a character to get two of.
Some of those traits are race traits, usually restricted to certain races. The FAQ is clarifying that, for example, a half-orc can pick half-orc and human race traits (although usually only one race trait per category can usually be selected; see Restrictions on Trait Selection). For example, a half-orc can pick the trait Almost Human (a half-orc racial trait) or Aspiring Bard (a human racial trait).
(Just in case, note that a member of a race only has available its race's racial traits to replace with alternate racial traits. That means, for example, a half-orc can't replace the human racial trait bonus feat with the alternate racial trait adoptive parentage because the half-orc just doesn't have the racial trait bonus feat. The FAQ's and so on could mean that were a racial trait shared by members of the half-whatever and whatever race, such a racial trait could possibly be replaced with an alternate racial trait that replaced such a racial trait from either the half-whatever side or the whatever side, but the GM must decide if the FAQ is, in fact, being that inclusive. Also, as of this writing, no such shared trait exists.)