Am I the only person who bluffs the customer when checking I.D.?

When working long night shifts I just asked for I.D. and couldn’t read the I.D. for people purchasing Tobacco and porn at a convenience store . I looked at the person and tried to sense whether the guy was trying to bluff me. Eye glasses don’t work and I needed sleep? What did you do to survive a long shift? I even hear that air traffic controllers are caught sleeping on the job. Are we asking too much from our employees?