but I myself am confused why the Owner always replaces the smart contract even though the token/coin is already known. what is the meaning of the tokens that have been distributed to participants, is it just for fun?
It's not for fun. This can be various reason who have been making the developers are always replacing their old token with the new tokens. I can mention some reasons as example
Just like these
1. The developers might found there was a crucial bug in their smartonctract
2. Scamming purpose
3. Avoid to the problem in short term.
There are so many reasons that used by the developers to replace their tokens. Investors are also feeling confused with it as developers are always swapping their tokens.