I hear you…and I agree with everyone who sees the nuances (colleges know about the hard schools). on the other hand, my kids attend a “tough” urban public high school…and my kid was 3 out of 300 in her class…and it did seem to help boost schools paying attention.
Also, just to speak out in favor of attending lower-ranked schools and seeking the best of it (i may actually start a thread about this 
but my kid (and the 2nd one too) received an excellent education…D1 ended up with a 33 ACT and an unweighted 4.0 .