There's really no way to know 100% why certain people hate Jews but it's probably because they hate the Jews Religion.
Just like some people hate black people and are racist some people hate Jews and that is their right to do so.
Just like you might hate something else while I like that same thing you hate.
Some people just hate the Jews while other people like the Jews or may not like the Jews but tolerate them.
People probably hate the Jews because like I said above it probably has to do with the Jews religion and those other people think the Jews are wrong in their religion.