True. Once you Pasken a certain way, the other way is not Kesidro. But until you crystalize a Shita people take it their own way. Now that there are these Shitos and there is a Taam in both, although the main Halacha is like Rashi, the other one is put on in the form of Chashash.
However, Chashashos aren’t chosen at random. When there is a big Netiya to a certain Tzad, Poskim would say that it is Kedai to be Choshesh for it. Understanding the Inyan for the other Tzad is no less than this.