Serious question --- if you consider the point of view of somebody like OP, who wishes he had more photos to help him remember and reflect on time he spent with his cherished now-deceased loved one, vs. your brief discomfort at having to stand in place for under a minute, and briefly have to contemplate the uncomfortable fact that you exist and are perceived by other people ----- OP wins. Every time. Consent plays no part in this, and if you honestly bring that up as a reason to finagle out of a class, family, or friendgroup photo, you are not only being very disingenuous but revealing a very diseased view of everyday life.