But he said this approach was not solving the problem and called for more effective alternatives to prison.
The LibDem MP said in 2002 a total of 16,620 shoplifters - out of 60,074 convictions - were jailed.
That compared with 2,514 imprisonments out of 50,858 convicted in 1992.
Oaten claimed that the high imprisonment rate was not just failing to solve the problem but was proving expensive.
“Most people would agree shoplifters are pathetic rather than dangerous,” he said.
The alternative, he suggested, would be for the government to advise retailers on designing out the risks.
Also, he wanted to see greater use of tough community sentences, CCTV, security and security tags.
The cost of imprisoning a shoplifter is about £750 a week. “Putting these people in prison for a few weeks is a pointless waste of taxpayers’ money,” said Oaten.