Talmud Pesachim

Rabbi Akiva says [in pesachim 5a] that the verse "make the unleavened bread rest on the first day" has to refer to the fourteenth of Nisan because other wise it would conflict with the verse that says one can't burn anything on a festival except in the case one needs to cook .

Why cant we say like we do for doing sacrifices on Shabat that this verse says that even though you can't do normal burning on Yom Tov [the festival] but in case of burning leavened bread- chametz there is an exception.

Because then we would have to split up the verse "make to rest". If the verse would only say burn unleavened bread only for need, then everything would be fine. But that can't be what the verse means. The main intention is to burn the bread not for any need but rather to get rid of it.