Generally speaking the more we make the more GST we pay and as you show above eBay are making more $ on their new fee structure and so pay more GST.
eBay used to hand over $9,900 to the ATO as GST on $99,000 in collected fees.
Under MP.....eBay hand over $12,180 to the ATO as GST on $121,800

So if eBay are collecting more fees per $1000000 then where are those extra fees coming from .....the sellers pockets ?

Are you an online seller k1ooo-slr-sales ?