One way or another, "sick days + vacation days" is strictly (and severely) bounded in most U.S. companies. You only have so many days in the year for dentists

One way or another, "sick days + vacation days" is strictly (and severely) bounded in most U.S. companies. You only have so many days in the year for dentists appointments, going with your kids to their appointments, etc. So the bottom line is that full day interviews are quite expensive to take for most people.