Re: Lesser of two evils?
"would need or want such information in the first place?"
Pretty much everybody has secrets and thus leverage. Some more than others, but in the right context that semi drunken fling with the office intern a decade ago could end a person's career (and possibly marriage) if presented in the right light. Unless.... they do this little favour and it'll all go away and be forgotten.
Remember - knowledge is power, and if one gathers enough information and gives it a shake, some useful things will fall out.