I would expect it to be the reverse: there is no incentive for government programs to root out fraud, if they fall short, they just raise taxes. For private companies - if they are being defrauded, it directly affects their bottom line, and the bottom line of their executives (who would be VERY interested to make sure bonuses increase).

If we are talking about fraud within the company/government, I would expect the same - less in the company than in the government. Not zero, but less overall.