Unfortunately, the answer is yes.
With a lot of money on the line, people can act badly and try to cheat fellow players. Lottery pool members have been sued for various reasons, including conflicts over who participated in the pool, whether tickets were purchased privately or for the group, whether the proper numbers were played, and more.
There have also been cases where unscrupulous people collected money for lottery pools then pocketed the cash without ever buying the tickets. These problems can be avoided with a little preparation.