Yes! Just upload a logo file in the Overlays and Titles section of the event snapshot page:
Then, go to Gallery Details and check the "Force Overlay" option:
*Since the overlay tool accommodates more than one overlay option, the first overlay uploaded to the event will be the one forced on all orders. If you have more than one overlay uploaded and need to change this, you have to delete all overlays and upload the one you want forced on your orders first.
**Note that this tool only applies to prints and products which are ordered through the e-commerce system. This tool is separate from the Branded Image Service downloads.