Why were the Russian Facebook ads so strange?

Last week, as Facebook testified before Congress about Russian meddling in the 2016 election, committees released the first batch of Kremlin-linked ads that ran on the platform. They were much weirder than anyone expected. There was plenty of straightforward political button-pushing, of course — the groups put forth both faux-Black Lives Matter and gun rights campaigns — but some of the ads were harder to explain. One ad put forward a Speedo-clad Bernie Sanders, lifted from a real-li