Your uncle is not doing the right thing because he's always hiding something that you already saw him doing the best thing he should do I not to smoke around the house areas if he doesn't want you or any of your siblings to know about his smoking lifestyle. It is better you don't have an idea that he smokes than seeing him doing it one day you may decide to always hide to know how just he's been doing taste and that is how kids learn how to smoke. Kids are fast learners, parents should learn to hide whenever they do the things they don't want their children or kids around them to not to emulate it is between they don't even do such things.
You have a point, because a lot of people don't know the vacuum that is being created when these kids eventually found out that their dad smokes. Just imagine if you find out that a very quiet and well mannered dude in your neighborhood is actually into things you never thought of him, that alone can create a vacuum, which a lot of children might eventually struggle to handle because they aren't matured enough. I would prefer that parents should smoke very far away
(not even around their premises), if they truly want to set a false standards that can at least keep the children away from such lifestyle.