It used to be true that we couldn't see the photo until we indicated on ERAS that an invitation had been issued. That changed several years ago so that now the photo is an element of the application that can be screened or not (along with things like race/ethnicity, gender, date of birth, social security number, and a few other items). The screen can be added or removed at any point in time, but that choice applies to all of the applicants.
During this early part of the process I keep the photo screen on and it's not a big deal to me whether we have your picture or not. When interviews start, however, I need the photo to put with your file and it will become a very big deal if you didn't send me one. It's honestly too much of a pain to turn the screen on and off depending on the reason I'm accessing an applicant page, so at some point I'll just leave the screen off and will see all of the photos regardless of whether or not we offered an interview.
For the record, I much preferred the old way ERAS was set up.