Limited packages can be obtained anytime in older versions of Minecraft

Hello i found a bug with that you can get limited packs anytime (example: Founder's cape)
thats why i make it private so people cant use it
steps how to do it (for pc)
1) uninstall Minecraft
2)install version 16.2.1 (it works on some olders too)
3) Go to minecraft.net page with pack (https://www.minecraft.net/en-us/pdp?id=b3b50166-5612-4ff1-8f03-9af0b01cb4da )
4) click 'get this item'
5) buy it in game
6) uninstall this version and install the lateast
7) Now Founder's cape will appear in capes tab

it also works on Android phone btw