A possible different approach: Rather than use Filtering to choose your block groups, if you have an Organization account and so can use the Analysis features of AGO, you could perhaps make a layer showing the boundaries of your trade area, then use Extract Data (in the Manage Data group) to pull out the BGs that fall in that area. Of course this means you are selecting the BGs geographically instead of using a list, so maybe this fits what you need or maybe not.