Restaurant and utensils

Question

If I am given a kosher meal in a non-kosher restaurant, can I use the restaurant's dishes? Although we say setam kelim einam benei yomam, I thought that since a restaurant is constantly using the dishes over and over again (unlike a caterer), we might assume on the contrary, that the dishes were indeed used for non-kosher in the previous 24 hours. What is the halakhah?