It's better for one to learn how to plan on money at hand and not on promises and assumption.
There is one lesson to learn here, never spend money that you do not have yet. You friend probably learned his lesson on your given incident.
Situations like this can teach you a valuable lesson not to rely on someone's promise especially when you are both drunk the night you got the offer.
Yes..., it really teaches alot of lesson. But yet most people are not still ready to learn from their past mistakes. They still go ahead living their lifestyles in friends, family and neighborhood promises.
They don't learn because they are able to solve it and deliver the solution to the problem. I think instead of learning from their mistake, they became comfortable and confident that they can fix it so for them it does not matter to repeat such an incident. These people will only learn if they are deeply in debt and unable to escape from it. Regret always happen in the end.
An example about a friend who spends for an early celebration is very upsetting when he found out he actually didn't win, yet he already spend money for the celebration. I would probably share an amount just to cheer up that friend.
That was exactly what we did. We are all friends so a shame on anyone of us is a shame on all.
It is not bad to help a friend especially when it is in an actual incident. We should really give some money as a share for paying the bill, after all, we had enjoyed the celebration and the food.