For perspective, here is a current listing of the number of tickets available on Ticket exchanges (from season ticket holders) around the league.
802 --- Vikings at Packers
2,728 -- Bears at Panthers
2,170 -- Browns at Titans
2,064 -- Rams at Eagles
1,802 -- Falcons at Giants
4,588 -- Buccaneers at Saints
2,414 -- Texans at Cowboys
3,823 -- Bills at Lions
1,738 -- Ravens at Colts
1,053 -- Steelers at Jaguars
1,161 -- Cardinals at Broncos
5,668 -- Chiefs at Niners
4,837 -- Jets at Chargers
4,226 -- Seattle at Washington
Considering this is a night game and the results of the most recent game, the number of tickets available is not out of line at all. For various reasons there are a number of tickets available at every stadium, every week. To imply that there are (or should be) no tickets available the week before an NFL game is simply not factually true.