American films were generally that way under the Hays Code which stipulated the antagonists in a film had to reap the consequences of their bad actions, either being killed, caught, or at a minimum, undergoing repentance and atonement.
One criticism of Frank Capra and Jimmy Stewart's, "It's A Wonderful Life," is that it was in violation of this element of the code, in that Mr. Potter never faced repercussions for his greed and theft of George Bailey's money.
You haven’t seen SNL’s lost ending to “It’s A Wonderful Life”, have you ? ;-D