When you register and Item there should be always a name and price because it needs that info as shown:
PHP Code:
native register_item(const name[], cost = -1)
If you set only the name, plugin will get confused because you left 'cost' empty.
If you set only price, the plugin will get confused again because you left 'name' empty.
So why I must set price in native if i can't use it as a default value?