Do I really need a two-factor auth to purchase gold?

I got this message when trying to buy gold with coins...

https://imgur.com/a/eETuKHP

i am really confused. why? because what if i dont want to use two-factor auth each time to log into the game? any way around this?...

wow. so now that I enabled it I get the message that I must have it enabled 3 days before buying gold. pffff.... oh well...

Yes, you do really need it, it's there to prevent someone from entering your account, sending coins to themselves and you complaining on the forums.
You can uncheck the little checkbox under Account->Security which says "Enable in-game protection" so you won't be asked for auth code when logging in into the game, only the website.
Even if it is checked they remember the last IP so once you've logged in from that IP you won't be asked until your IP changes. Depending on your ISP or network that can be quite a while. Mine is almost static, changes like once every few months.