To anyone who claims to not be spiritual, I ask: do you believe in a right and wrong? Do you have preferences? If so, then you are spiritual.
You may be materialistic and feel there is nothing more to existence than physical reality. You may believe furthermore that every feeling or sentiment is nothing more that chemicals reacting to external stimuli and energy, all of which originates from some big bang or whatever else we’ll discover. But the observable truth is that we do “feel” emotions and consistently choose to actively favour certain states and avoid others. We exist, we feel, we matter. That is spiritual.
Spirituality doesn’t mean you use essential oils or pray. It means you believe in an IDEA. Ideas don’t exist, yet they affect us, guide us.
Inert matter cares not whether it is respected or loved. It does not have a preferred state outside of what is imposed upon it. It will settle into balance and nothing else.
So, do you have a favourite flavour of ice cream? Do you even like ice cream? It may be that your biology or the physical organization of your “being” dictates how certain stimuli would provoke you in specific ways. But you have a preference, a path you will follow. You have a “spirit” guiding you.