I'm willing to bet that Super Paper Mario underperforms in Japan and doesn't have the legs of long-time sellers like SMB. Check back after the second week figures are here.
Initial sales of it in the US aren't exactly record breaking, and it stands a better chance there than it does in Japan.
The Final Fantasy remake should do fine considering that the GBA version was only released 2 years ago and sold very well back then. There are only so many times you can sell the same game. I picked the remake up myself as I have never played FFI before. I think good word of mouth will be factor to give some legs to that title. Personally, I love it.
PSN - hanafuda