That assumes they want to escalate. So far at least their official statements have been clear about tit-for-tat.

It could also backfire spectacularly. If a bunch of civilians suddenly get killed or other war crimes committed unilaterally by them (such as targeting energy infrastructure) their adversaries could gain political support for the current effort. Whereas gradually forcing all interceptors to be expended is a massively expensive slow bleed and gives the opponent little to nothing to spin in their favor.