This is correct. Generally the more you have staking the higher your odds of getting a staking reward. Right now the estimated amount to get an average 1 stake per day is around 16,000 zerocoin veil.
How much does it cost with 16,000 Zerocoin VEIL? At the current price of VEIL, it equals to 0.21 BTC for 16,000 VEIL, and at the staking rate (50 VEIL received per day), it will take around 320 days to receive 16,000 VEIL back from staking. It still does not count for the increase of difficulty over time.
Yes, within a short period of time it is impossible to make a profit on the investment and every time we cannot make the same amount because once the development team is doing good then the community will start buying a huge amount of coins for staking.