Yes, vegans can eat most canned beans. The challenge becomes refried beans in particular. Many brands of refried beans add lard to their recipe. Lard is that fat from pigs. When choosing a brand of refried beans take a look at the ingredient label to be sure lard has not been added. There are many varieties that say "vegetarian" on the front, in which case lard has not been added. Most other canned bean varieties do not have added animal ingredients, but do include other ingredients, often water, salt, and sometimes sugar.