When we lived in southern Nevada, our local major supermarket decided to go all out with Passover displays. Visitors from Los Angeles said the selection was better in Nevada. Before then, Jewish residents of the area had relatives send them supplies, or made shopping expeditions to Southern California.
That first year I watched people fill two or three carts with products ranging from Passover marshmallows, potato chips, jalapeno gefilte fish (for real - it was their biggest seller that year!), Israeli and domestic specialty items of all kinds. One friend bought out their entire supply of chocolate-covered marshmallow twists and froze them!
I even remember another long-time Vegas resident, just standing in front of the display, weeping tears of amazement at the variety.
Following Chabad's arrival in town, fresh kosher meat was sold in several supermarkets in areas of greater Las Vegas area where most Jewish families lived. This was a major improvement over having meat shipped in from Los Angeles or Phoenix.
Florida Jews, according to this story, appear to be the beneficiaries of a supermarket struggle over the market for kosher food, with chains including Winn-Dixie, Publix and Albertsons adding kosher delis and kosher bakeries in addition to kosher meats.