Splitting a CNC order results in reduced charges. Reasons?

Zerodha
1

I noticed this that when you put a CNC limit/market order and if you split this in smaller amounts, you probably have to pay lesser charges (tax & others) compared to if you were buying in bulk
Here is a small example.
GOLDBEES with 100 quantity charges 7.28

bulk_order

GOLDBEES with 50 quantity charges 3.14

split_order

So if you put 2 split orders of quantity 50 each, you will cumulatively be charged 6.28 rupees on this order compared to 7.28 in bulk order
Is this a known phenomenon? What causes this?

When I put these numbers through Brokerage calculator – Zerodha, results are same.

Is there an optimum split that I should do, rather than placing a bulk order?

2

Interesting observation

But is it worth the hassle of placing multiple orders?

In attempt to save 1-1.5 rs in charges by placing multiple orders, if price moves up, it hurts more than paying one time charge many a times.

3

But this is just an example of a very small order to show the phenomenon. Not sure what could be the savings for bigger orders.