Although this is true, I've experienced my times be incorrect more than once this year, and it's frustrating and gives you doubt about the system as a whole -- if my time can be wrong by 5 minutes, who's to say the places are correct? Our race series needs credibility, first and foremost, and while I don't want to spend more, I can easily justify spending $30 for trusted results as opposed to a suspect $25.
Your times are probably right, they just stagger the field or start late. The posted times for the race Sunday were as if everyone had started at the same time. So I pulled a 1:30:25 or whatever but that was 4-5 minutes after the lead group went off. All that matters is how I placed in regards to the guy before/after me.
I will say that some races will say, "Subtract X for real time," which would be an easy "fix" for this. But if every racer in your group complains they were scored 5 minutes slowly, it probably just means that group started 5 minutes later than they marked it as.