Why do people still smoke cigarettes in front of you despite knowing its harmful to you as a non smoker?

I've long since wondered why people smoke cigarettes in their homes when they have company over or at all for that matter. I mean I used to smoke cigarettes, but I never once thought about smoking them inside the house because I have always been extremely repulsed by the smell. Isn't everyone? I guess now that I don't smoke it easy to be more critical of smokers but I've been dealing with it my whole life and frankly, I'm fucking over it.

My mother was a cigarette smoker on and off but ALWAYS smoked the cigarettes with us kids in the car. We often went to restaurants where smoking was allowed. Then gradually society seemed to catch on to the fact that, "hmm maybe we shouldn't force other people who don't smoke cigarettes or don't want to be around them to BREATHE in our second hand smoke considering we ALL know at this point its not good" and so laws were created which prohibited people from smoking inside. Though people still smoke in bars in some places, I know most of the places I am eating food I don't have breathe other people's smoke. But it does beg the question, Why the fuck do people continue to, despite knowing they are directly harming people (especially those they claim to love or care about) smoke in front of those who don't? I am at a loss, seems like if you accept a ride now a days you are signing some hidden social contract that says "yeah go ahead and expose me to more carcinogens then I already am exposed to daily without my consent". I can remember asking my mother not to smoke in front of me but it never seemed to matter. Cigarette smokers get all defensive about "their right" to fuck up their bodies and all that shit and some even have the audacity to say "if you don't like it leave". Now to be fair, plenty of people will quickly just put the cigarette out if you ask. But there in lies the problem, IF you ask, then someone might decide to be considerate. If you DON'T ask somehow you are subjecting yourself to some hidden social contract and are expected to, it would appear by the vast majority of humans who smoke cigarettes, just put up with it. Well I've been "putting up with it" my whole life and just about the only solution I can think of is to be 100 percent self reliant and also very verbally assertive about certain things which can be uncomfortable for some, especially when people play fucking games and act like they forget that they are being inconsiderate.

That being said, yes this is just a rant. This is just my opinion. I've thought long and hard about it for years. YEARS! I've wanted to make a public post for all my friends to read just to kind of promote awareness, like actually being aware of your actions and not acting mindlessly as most people are. Yes I am frustrated. Perhaps for reasons aside from just this extreme pet peeve of mine. But GOD DAMN IT PEOPLE STOP MAKING US BREATHE IN YOUR DAMN CIGARETTES . UUGHH! I will be moving into my tiny home shortly and hoping to be in more control of my environment...as you might can tell I live with, yep you guessed it, cigarettes smokers. Some might say "why not just avoid hanging out with people who smoke". It's just simply not that easy. There are SO many people I DEEPLY care about who smoke but I still love them. Most of them are considerate...most ;)
Well that about wraps it up for this post. I wish I could truly make an impact on the world and inspire people to be more considerate. I know it starts with me but hey, I AM leading by example. I'm just waiting for some of yall to catch up. I don't mean to insult or harass or bully or offend anyone with this post. I just think it's about time people give just a little bit more of a shit about each other. We could start with the cigarettes. Don't get me started on the fact that people throw them all over the fucking ground!