Florean Fortesque, Why did voldy take him??? Options

[mischief managed]

I have been re'reading the hp books, as i am sure every true harry potter fan has, and i realized as i was on HBP, no one really elabortaed on the reason Florean Fortesque was kid-napped. I am quite sure Voldemort kid-napped florean, but for what reason, i asked myself?

Then, as i was re-reading the third book, (i read the series from front to back to notice patterns) Harry had stated that he got quite a bit of advice on witch hunts from Florean for harry's history of Magic homework. Perhaps this is why voldemort took Florean, because voldy was planning on using old, and stealthy method of hunting his wizarding victims. Perhaps he wanted all the facts on witch hunting. Looking into the past to not make the same mistake people in the medievil days made when hunting witches stealthily.

I have always wondered why no one elaborated on voldy's reasons for Florean being kid-napped. Please give some other input