Your fruit brought over some sugars, raising the gravity. I thought generally that the sugars in fruit were almost entirely fermentable, but I suppose that its possible that you didn't have enough yeast left in suspension after transferring to fully ferment out all the extra sugars. The other option is that there were some unfermentable sugars/compounds (pectin?) that raised it slightly.
Of course, there's also the chance that its not actually higher and this was just a screwy reading. Maybe the temps were a little bit different, or maybe there was enough CO2 in solution after the fruit to nucleate on the hydrometer and raise it a little bit. Since you're kegging, a little extra sugar won't hurt anything, and so long as it tastes good I would just RDWHAHB .