I agree that the rules are pretty complicated and on top of that they are very extensive. Most players probably don't know every single detail, but that's why we have the rules in every game topic. You can look up everything you don't know off the top of your head.
However, I still think it is crucial that players be aware of a good chunk of the rules. In Mafia it is vital that you understand what an ally of you would have to gain by lying to you, and how you can catch him or her in that lie. And also what it would take for the Black Organization to "prove" the lie to you. If you are evil, it's important to know how easy it would be for people you're lying to to see through it, in order to see how risky different plays are.
Ultimately, the more you understand the rules, the more likely it is that you are able to successfully deceive if you're evil, or successfully pick out those that are trying to deceive you when they are.
Usually, you learn as you go along. This round we had a lot of lpayers who haven't had much experience with the game yet. It's understandable that there are many things that didn't immediately make sense.
I hope you guys will be back when the next rounds of Mafia start, and I encourage you to come by #minimafia at Rizon where we sometimes play Mafia, though the rules differ somewhat. One thing I can say for certain: The bigger your understanding of the rules, the better you will be at this game and the more fun it'll be to play.
"Vad ska jag annars vara?" - "Det vet jag inte. Det måste du svara på. Men om du släpper allt du tror att du måste, och frågar dig vad du vill... Vad vill du då?"