T shirts looked better than the usual offer for large sizes. These shirts are not the ones in the website, looks like last seasons line. The one I've linked with is white with diamonds was also in Blue and Red M-3XL. Others were similar colors to this (blues, greens, red etc) Link but had things like "baseball"/continental necklines, so three buttons at the top or plain necklines.
Other than that, there were Joe & Co larger sized raglan shirts for $5 Link and $10 Aerosmith/band tees (usual price but not a bad shirt) Link
Ymmv per store.
The band t-shirts are pretty nice for BigW. Picked up a couple early last year in Victoria for son; Pink Floyd etc.