Thanks to twitter, and spotter @lacorbeau, I've found some evidence that can defend this choice. It's commonly accepted that confronted to nudity in ads, men would spend more time looking at female bodies than women would. Research firm EyeTrackShop recently surveyed both gender to find out.
And it's not always that obvious (click on pics to have a better view):
Women actually looked at the torso before looking at the face. But there's more:
In two stimuli showing less-dressed or naked persons men looked at the faces about 40% longer than the women did and it's the first area noticed. When looking at a naked model, there are smaller differences than one would expect:
Again, the greatest differences were found in how long respondents choose to look at a specific area:
Conclusion? Almost all women fixated on the shoes and spent almost 1.5 seconds on them. So:
"Using an undressed model to sell shoes to women could definitely do the trick"Source: Business Insider - EyeTrackShop report (links)