That’s an excellent question. And a pet peeve of mine. There is a concept in Judaism that translates into building a fence around the Torah. Based on the law requiring one to put a railing on their roof, so that if someone were to go on the roof, they wouldn’t fall off. In short, this concept means that at times we make laws that are designed to prevent someone from breaking the real law. An example is the prohibition against carrying money on the sabbath. Now, there’s nothing in the Torah that suggests carrying money on the sabbath breaks a commandment. But the rabbis were concerned that if you carry money on the sabbath, you will be tempted to engage in commerce (maybe stopping at the local lemonade stand on the way to synagouge). So they made a law saying don’t carry money.
I think that, around 1100 CE, the rabbis became concerned that if a Jew saw another jew eating chicken parm, they might mistakenly think he was eating veal parm. And that since his pious neighbor was eating veal parm, then eating veal parm must be ok. So to prevent this extremely likely scenario from happening

we came up with the no chicken parm law.
As someone who is half Italian, I’m not crazy about it.