I feel that 'elitism' is, most of the time, not necessary at all for certain occupations. Your education will of course be important although they should not categorise establishments.
Scenario 1 and 2 are fine so long as that's what the job requires.
3 is borderline but 3 and 4, in my opinion, should not categorise certain establishments.
Scenario 5, as said, is purely racism and in this current society is not and should not be tolerated.