Offcourse, you can invest into HYIP's which gives high profits, but it's too risky to invest, because we will just loose our money.
I think it's better to deposit bitcoins to freebitco.in than just hold bitcoins in wallet. Profit isn't big, but it's safe to invest and we can earn some passive income.
There is no guarantees that you will earn passive income in any kind of investment. There is always a risk to lose our investment by some cases such as site getting hacked or other things. I dont really understand how the investment on freebitco.in works but I guess they cant give you guarantee of profit. It will be suspicious if a site offering guaranteed profit on investment.