Ask HN: Do you sell your software to everyone?

Many of the great products the HN community puts out really help businesses be more productive, increase sales etc.

But do you just allow your software to benefit anyone who signs up or would you restrict certain types of people or businesses.

I know we would all remove spammers, or businesses doing illegal things but what about say a Tobacco company?

We know their product kills and is detrimental to society. Would you want your product to help them create better sales or increased profits?

And where do you draw the line?