This is how it works, type 0 will decide how many items can be seen with no error on other types ( 1 -7 ).
For example , I put 5 items on type 0 then i put 7 items on type 1. only first 5 items will be seen with no error.
This is a common bug because cash shop support in rAthena is not that high compared to hercules, well atleast i got this info credits to Brynner. But he's pretty much correct
+ 1 to LatSo's reply.