The other side of that particular coin are Augsburg, Berlin, Bochum, Darmstadt, Heidenheim, Hoffenheim, Leverkusen, Mainz and Wolfsburg in the first division. It will probably be just an anomaly.Meanwhile here are the first attendance numbers for the 2. Bundesliga.
VEREIN ZUSCH./SP. Schalke 61.801 HSV 57.000 K'lautern 44.079 Düsseldorf 40.466 Hertha 40.075 Karlsruhe 33.000 Nürnberg 30.012 St. Pauli 29.546 Hannover 29.200 Rostock 29.000 Magdeburg 28.350 Braunschweig 20.002 Osnabrück 15.741 Paderborn 14.789 Kiel 11.790 Fürth 10.547 Elversberg 8.371 Wiesbaden 7.219
That gives us an impressive average of 28.388 spectators per game and it could be even better if there weren't 6 clubs with tiny stadiums in the league. If Dresden had been promoted instead of Wiesbaden we'd be looking at a higher average than La Liga and the Serie A.