Agreed. Very frustrating.
I can tell you all from personal experience as a transfer, and from second hand accounts of at least a dozen other pre-meds that were in my transfer class, that many-a-4.0 dropped below 3.5 after transferring to a rigorous university for pre-meds (<15% acceptance rate and 50% range for ACT is 33-35 to give you perspective). In fact, I was just talking to my friend today who transferred from ASU, and she remarked that she had a 4.0 there with minimal studying (i.e. only the night before) but a 3.3 here while studying harder. I've heard the same from friends that transferred from UI-UC, Villanova, Syracuse, UT, and many others. No one is saying that all students at top schools are smarter than all students at lower ranked schools. In fact, I have many friends at unranked schools that I consider more intelligent than myself. It's just that the students (at Hopkins for example) are all hard working and very intelligent, while you get more variation at 95% of universities. With no grade inflation, this means plenty of smart kids get mediocre grades (usually only 15-20% allowed in the A/A- range). Admissions is not very forgiving of this either, which is why you encounter such strong opinions on the subject.