they can make changes if they want to because that 4percent interest per year can mean alot if price of btc pump too much but scammers doesnt affect it or you mean abusers that make many acounts to abused this feature ? that can still be useless because they still need to put money , they need to dedicate time . that just simply not worth it
Annual interest for 4% isn't changeable. It's fixed.
He meant there will be new site pop up trying to copy freebitcoin's offer and then many people could be get scammed. What's the point to make multiple accounts and then all invested on freebitcoin? Doesn't make sense