Illegal means against the law or against the rules. A crime is a function of how severe your illegal action is.
Put it another way, people think if something is illegal, punishment for that must be a felony or something. But often times, it’s just an infraction so punishment is at most a fine or a minor action like getting kicked off the free beach
many people do think that since they make a big deal out of Airbnb and Uber doing something illegal - not realizing that the illegality of what they did is equivalent to getting a parking ticket.
