I said you lie as town because that's a thing so rare over here that it's worth mentioning. It doesn't mean that I think you're lying, therefore I think you're town, that's not my logic here at all. It means that the possibilities are a) you're town and telling the truth, b) you're town and lying about your role again for some reason or c) you could also be scum in which case I would expect you to lie about stuff anyway.
As for why you might lie about your role as town, fucking beats me, I don't understand why you'd do it but the fact of the matter is you do it anyway. One reason I could think of is that perhaps you've got a very strong role and claimed Miller so scum think you're not a priority and not worth killing/blocking for some time. That's about the end of good reasons for lying about your role again that I can think of though.