Should I tell me parents I'm dropping out or just do it?

So they already know I want to drop out of the university I'm enrolled at (I've found a course at a different one I want to do in September), however they want me to finish this year and then transfer rather than drop out because it'll look better on my application. Although I spoke to the university and they told me it makes no difference whether I'm a late applicant or a transfer.

Thing is, I can't be dealing with all the money I'll waste by staying here for another term, my parents don't care about paying my accommodation bill, but at the end of the day it's another 3-4 grand I'll eventually have to pay back in tuition loans.

So I've pretty much decided to drop out and leave and reapply to a new uni as a late applicant. However I can't bring myself to call them and tell them, because the last few discussions we've had about it all revolve around them basically telling me no, that I need to finish the year.

I know it's my call, they can't stop me, but I genuinely can't confront them, I know if I call and try to assert myself about the decision they'll just shoot me down again. So I'm left with barely any options, do I attempt the call to try and convince them even though I already know how it'll end? Or do I just drop out without telling them since there's nothing they can do once it's done?