Most pharmacies in the US sell beer/wine. I don't think that is the case for hard liquor, though.
RiteAid sells hard liquor in Washington state.
I guess it makes sense it would be legal in states where the sale of hard liquor is allowed in places outside of dedicated liquor stores (and WA is one of them), I've just never really noticed it (never been to RiteAid in WA, though, only to Bartells/CVS/Walgreens). Thanks for the correction.