buying supporter packs more expensive on steam

like the title suggests, prices on the main PoE website (pathofexile.com) are inclusive of sales tax, if u buy a supporter pack via Steam, you will be charged sales tax again, making steam 13% more expensive atleast in Ontario. you can verify this is true by attempting to checkout on both websites, just wanted to let everyone else know so they aren't paying 13% more for no reason.

just wanted to bump this with updated information i think would help some people,

apparently, buying PoE MTX on the Epic Games Store the prices are calculated correctly before tax, so this issue seems to only be limited to STEAM for whatever reason.