The 2013 WCC drew 303,000 - that was a Friday night though. 2014's game was on a Saturday morning, but still drew 159,000.
The first couple of rounds of SL have been down compared with the first 2 rounds last year as well. Like differences in attendances though, there's numerous reasons for this. The Thursday night games seem to be getting hit by the darts - the PL Darts season started on the same night as SL and outdrew it by a fair bit.