How come?

How come I'm friends with you,
I don't even like you that much,
How come you're so expensive,
You're hardly even worth it,
How come I see you every day,
I always get in trouble for it,
How come i cant just leave you,
You keep on pulling me back,
How come you are so popular,
You're not even pretty or kind,
How come you're illegal,
How come you're so small,
How come you're so smelly,
How come you're so addictive,
How come you're so wrong,
How come you're a killing machine,
How come I haven't stated your name,
How come, well, your a cigarette.