Nothing happens if I get accepted into my 3rd choice , it's just my parents are forcing me to do the interviews alongside homework and all that , but I just don't see the logic , my mother says 'just in case' and thats all , but that just seems extremely irrational to me considering I've got a place set in concrete already in a BETTER college

No , because what happens if you got accepted into the 3rd one ? 

Ain't worth it

cancel the 3rd one and continue in the second.

1 . No 

2. College is free in my country

Is there anything to be learned/gained from the interview? What if college #3 offers a substantially better financial package?

I applied to 3 colleges , I was accepted by my 2nd choice college (2nd best) , but I have an interview to my 3rd choice (3rd best) college , is there any point in going now that I have been accepted by a better college , and that I don't want to go to the 3rd college anyway . BTW I have also done my 1st choice college interview.

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