Too old for YA Fiction

It really troubles me when adults say that "Young Adult" is their favorite genre.  Adults would never say "Baby food" is their favorite food.  Twentysomethings would never call "AARP" their favorite magazine.  Young Adult books are written for humans aged 12-18.  This isn't to say adults cannot read and appreciate them-- there are good ones out there!  An intelligent, moving book is an intelligent, moving book.  There seems to be a lot of serious YA fiction that is much more emotionally engaging and realistic than the majority of supposed "adult" fiction (James Patterson, etc).  But any adult who calls "Young Adult" their favorite genre can't be exclusively referring to those books.  They are talking about Divergent and Twilight.  They're talking about never growing up.  They're talking about being too impatient to read anything that requires a high school education.