2 games, 2 games in a row!

first game, day 1 a survivor reveals.
"i'll help town, i'm not voting".
i say day after a day to LYNCH this guy, no1 listens "its only a survivor".
i explain that it can be a mofo hiding as survivor, or real survivor that ALWAYS helps maf.
he begs that he will help town.
surprise - 2maf vs 2 town and a survivor, survivor HELPS MAF.

2nd game was amazingly annoying.
survivor claim at day 1,
each day i urge the town to lynch him, because he will help the mafia.
he swears he will help town, faking and "carrying" the town to "victory".
when he's the additional vote from town vs mafia - HE VOTES AGAINST TOWN.


WHY DO PEOPLE LET SURVIVORS LIVE?!?