In France, People have to show proof they have either been vaccinated, tested negative for Covid or have recovered from the disease in order to enter a museum, cinema, sports venue, travel on a long distance train, access a hospital, enter a café or any indoor place selling alcohol or food.
Black Market Covid Health Passes are becoming common.
https://www.france24.com/en/europe/20210818-black-market-for-fake-covid-health-passes-flourishes-in-france