According to an employee at Gold & Silver Pawn with whom we spoke, the History Channel films the show wildly out of continuity, so that what’s shot tomorrow might not be spliced in for months afterward or could just as easily go into the next episode. At any rate, you seem to have been the victim of poor continuity by the editors of the show. To answer the easy part of your question, no, no motels or wedding chapels have been demolished in that part of Las Vegas Boulevard.
However, the federal government is constructing an office building that would probably meet the specifications of what you saw. Situated on the southeast corner of Las Vegas Boulevard and Clark Street, it was begun on November 21, 2011. It will be eleven stories tall and, according to the Las Vegas Review-Journal "will house the executive and administrative offices of the Department of Homeland Security’s Immigration and Customs Enforcement (ICE) and the Federal Protective Service (FPS), U.S. attorney’s office for the District of Nevada, and the Department of Labor Office of Inspector General. The U.S. attorney’s office for Nevada will move from the Lloyd George U.S. Courthouse across the street to the new 11-story tower."
When completed, it will be called the Federal Justice Tower. According to City of Las Vegas Public Information Officer Margaret Kurtz, the planners of the building decided to put retail in on the first floor, thereby delaying construction while approval of the alteration made its way through federal red tape. This would explain why it couldn’t be seen when Pawn Stars went into production in 2009 and why it was seen in skeletal form in later episodes.
