If I'm desperate I ask "Can you front me some?"
And I always pay back.
Or my lil bro will say "get five/ten bucks and I'll make it worth your while"
and he always does.
If my best friend has enough to share, and I make it clear I'm in need of a smoke, she usually helps me out.
On the weekends, me and her smoke up everyone who comes over, usually for free of for 5 bucks.
If you don't have 5 bucks, you're an asshole.
Especially since we usually spend around 150$ each friday.