Who says that they are expected to be done in one’s “free time”? What responsibility or business is it of an employer to know how candidates are making time for

Who says that they are expected to be done in one’s “free time”? What responsibility or business is it of an employer to know how candidates are making time for the job interview process? If any non-zero time required to obtain a particular job is descriminatory then every existent hiring process is discriminatory. What do you suggest, drawing lots?