"There's a very clear line," Cramer said on "Squawk on the Street."
"I know I have to lose my job because of failure to supervise. The failure to supervise rules are so clear that there was no way that John could survive. He either knew about it and he had to be fired with no severance or he didn't know about it and he failed to supervise."
Cramer made his comments a day after Stumpf announced his retirement, effective immediately. The announcement came a month after Wells Fargo agreed to pay regulators $185 million for opening about 2 million accounts for customers who had never asked for them.
Stumpf said it was best for the company that he step aside.
The banks' board of directors elected President and Chief Operating Officer Tim Sloan to succeed Stumpf as CEO. Lead director Stephen Sanger will serve as the board's nonexecutive chairman.