In the United States, the Caesar is typically available at bars along the Canada–United States border. Elsewhere, bartenders will frequently offer a Bloody Mary in its place. In Europe, the drink can be found wherever there are higher concentrations of Canadians. The drink's anonymity outside Canada has continued in spite of concerted marketing efforts. Producers of clam-tomato juices have speculated that their beverages have been hampered by what they describe as the "clam barrier". They have found that consumers in the United States fear that there is too much clam in the beverages.