To me it’s a very smart approach, indeed, if you don’t have fees all user would store their coin in the private wallet, hence Sybil attack would be much easier to perform.

I really see how to use it in daily life, I receive funds on my public wallet, they are public, but as long as it’s not possible to link me with these transaction it’s all good.

So basically on my mobile wallet I will have my public and private wallet, I can transfer immediately some funds from my public to my private wallet, and they become untraceable as nor the transaction nor the balance can be accessed right ?
And  let say I go buy a coffee, I use my private wallet to pay, I’ll pay a small fee, and in the end of the day I’ll get back fees depending of my balance on my public wallet ? Hence it means If I spend coin using my private wallet my fees will be paid back, if I don’t spend I’ll be remunerated to delegate my vote to a representative, to me it sound amazing as long as the fee is low.

It's like a freemium version of Nano, it's like XRB for public transaction, but if you want another feature it's possible but for a very small fee.