Since I bought my SQ F and J flights via Aeroplan, i'll reply here

There are a number of threads on the SQ forum and elsewhere where people either asked why no PJs or complained.

One of the answers posted was along the lines of "I'd rather SQ continue to offer the best meals and service than waste money on PJs".

I agree. Slipper are always given in J even on intra-Asia. In the lav, there are various amenities. As for PJ's, the Lalique ones and full and fancy amenities and kits I received on SQ F were not really up there compared to the LH F, NH F for sure and also BR J.

Either way, I would also want AC to provide better quality slippers on TPAC or better quality eye-shades, but I'd rather airlines spend less on this stuff and more on the cabin and fight experience. In fact, BR J and NH J and F have all the things one needs available in the lavs on the counter. LX even had some items on the counter in their lavs on TATL.