The hex is for patching the memory when the game is running instead of patching the rom. (Used in DSTT and WoodR4)

I tried to find the corresponding place in the rom to edit for the respective patch in memory, and it seems there are some kind of rearrangement of instructions in the rom.

e.g.

mem offset @02049654

The unpatched game memory would look like this:
38 40 2D E9 00 0C A0 E1 21 24 80 E1

while in the rom @3B9510:
38 40 2D E9 70 30 9F E5 00 0C A0 E1 21 24 80 E1

The underlined instruction is being inserted in between.

p.s. There is only one place in the rom with 00 0C A0 E1 21 24 80 E1.

And to apply the patch to the rom, using the existing mem patch would become
38 40 2D E9 70 30 9F E5 00 0C A0 E1 21 24 80 E1 ->
00 0C A0 E1 70 30 9F E5 21 04 80 E1 00 10 A0 E3

The underlined section is kept to be the same.

And there are 13 other places to be patched, where one of them (the wall of hex provided above) are patched to an empty section in memory (the heap probably).

Conclusion: it would take quite a long time for a rom patch to appear I guess, I hope I am wrong though. XD