If your a dog specialist ANSWER!!!!!!!!?

is it bad to kiss dogs a lot? my friend does it so much. shell even let the dog drink out of the same cup and CONTINUE TO DRINK IT! she also says dogs mouths are clean and if you have a cut or a wound and don't have alchohol to clean it your dogs saliva can clean it. is it true? and is it of for her to kiss and stuff like that?