tbe - whats this 12.5 cent trading pattern?, page-18

hey Im a newbie thats fr sure, but how could it be viable to buy such small amounts, looking at my expenses to trade I would be losing money hand over fist, also I noted that some amounts seem to be available to some but NAB wont let me put those in eg 12.25 c I can only go 12 or 12.5%
is this all bot activity and if so maybe we should all buy a bot too LOL.....