It has been known grocery stores do not sponsor H1B in general. Well, they did in the past (small number of visas) but they cut that out way before chain pharmacies stop sponsoring visas.
CVS, WAG, and RAD stop sponsoring new H1B visas since ~2010. Your only bet to get H1B visa is to work a small independent who will probably pay you lower salary just at prevailing wage for that area (they know you are desperate). Prevailing wage sux because it can be as low as ~$10-15 less than what a retail pharmacist make. They also will most likely want you to pay your H1B visa out of your own pocket if they decide to hire you (this is illegal practice since employers have to pay in normal circumstances).
Residency is not an option because they need you to be GC holder at least. Some non-profit hospital or academia might sponsor H1B applicants although it's less likely due to the fact they have surplus pool of American Pharmacists. Why bother paying ~$5000 for any international student, dealing with an attorney and wasting time?
Good luck