If I zero out drive using traditional method - data is still recoverable.
If I zero out drive using random data - I can be suspect and/or get free rubber hose for life, trying to extract keys for something that doesn't even exist?
The authoritarians would like to be able to torture and imprison you based on nothing more than their whim, so that's why they set it up this way.
The authoritarians' apologists will probably note that to address your concerns, you should use random data first, to whatever extent you think will thwart recovery efforts, and then zero out your empty space.
If I zero out drive using traditional method - data is still recoverable.
If I zero out drive using random data - I can be suspect and/or get free rubber hose for life, trying to extract keys for something that doesn't even exist?