The problem with applying to "lower tiered" schools is the fact that, if you get accepted, you'll (typically) have to pay a deposit within 2 weeks of admission. Furthermore, those "lower tiered" schools have much larger deposits. Therefore, if you have thousands of dollars to blow on deposits that you have no intention of keeping if you get accepted to a "higher tiered" school, then go for it. 😱
Couple that fact with the common knowledge that you can't schedule your interview date unless you have extenuating circumstances ... you're a bit of a fool to apply to schools that you don't wish to attend because you'll be wasting thousands of dollars. If your parents are paying for your expedition, it's one thing. However, if you are paying for it yourself, you will be less apt to blow money on schools.
I'm all for pursuing mock interviews, however, it's an expensive road to hoe financially, especially if you don't want to attend the school or if it is a last resort option. The fact of paying deposits and being financially self-reliant has played a large role with my application process.