Quote Originally Posted by Zfz View Post
It's probably because 99<128, and 128 is one byte. To allow a stack of 999, it will require two bytes to store the quantity, which literally means doubling the storage space needed for every player. But I'm just guessing. It's as likely to be just a design to force people to have inventory problems, as inventory management have always been part of a lot of RPGs.
One byte holds 256 "numbers". Increasing stack size to 200 would not require them to do anything more than increase the limit. Unless they're using signed integers for god knows what reason for item stacks.

Increasing the inventory data by one byte for every registered 4 million users -- let's even say everyone has two characters -- would increase the size needed to store all of the extra invetory by less than seven gigabytes for every account and character combined. And that is only if every character on every account would use all of their extra possible inventory space fully. Inventory space requirements is almost nothing compared to what other data they need to store.