Are “American” groceries available in Subic Bay?
Yes, but not as extensively as one might wish. There is a large grocery store a couple miles Binictican Housing, called Royal Subic, with another just next door to it, and they provides most staple and dry items. Vegetables, fruits, and some meat (all chicken and pork) can be bought at the large open-air public market in Olongapo. Those items can be bought straight from a vendor (with good quality and at low cost).