It's a because you're not understanding what the interest is for, who's paying it or who's receiving it.

In VIVA new money isn't just printed out of thin air. It comes from somewhere.
Only mints can print viva, but they have to pay for the right to do this.
If you have enough money to run a mint on your own, then the money you pay for the exclusive right to mint this money is just a cost of doing business.

If it helps to think through this, then flip it on it's head and look at it this way.
100% of all future VIVA is owned by people in the future.

The mint operator which is always a business, is borrowing from VIVA holders (individuals like yourself).
The money they pay to do this is given to you the individual, with the catch that you use it help others.

This is because there is no way that you an individual sitting at home are going to be able to compete for long with a business who's purpose is to print cash. So we reduce the supply to keep the price of the coin higher and use that reduction in supply to give to you more in the future.

But you get this, slowly, over time, when you're ready to start receiving your daily dividend payment.

This is not at all the same thing as taking out a loan. For instance a mint doesn't pay this amount back directly and they aren't under any obligation to pay it back. Instead they are minting new money that feeds back into the system by paying worker nodes and subsidizing business activities.

Interest is used as a control mechanism to prevent currency supplies from spiraling out of control, by contracting i.e. reducing supplies.