I don't believe that a man HAVE to pay for a date's friend, if he doesn't want to pay. That isn't an unspoken rule. Some men feel "manly" doing shyt like that. These men think it is "chivarous" to do such a thing, I guess???
My issue with these types of rules is that rules seem to apply only to men. Men are supposed to do this, that and a third, but at the same token, is also said that a man shouldn't expect anything in return.
Since when does someone does something and doesn't expect anything in return? Businesses don't do it. Utility companies don't do it. Women certainly don't do it!
Anyone who invests in something wants a return on their investment!
Lastly, why would anyone want to be a third wheel? How come that person can't find something else to do or better yet find someone else to do whatever with? Last thing any person need is someone posing as a potential cock blocker telling someone that he needs to do something for that person. Smh..
Any man who chooses to pay for the "house" sort of speak can do so. His choice. But, it certainly isn't a rule!