I fly freight around in the Irish Concorde and I haven't seen an ATCO near the aeroplane in 6 months (ie that's how long I've been flying the beasties).
I am not suprised. The jump seat is tiny and there's no catering.
I would happily fly with an ATCO sitting there.
Perhaps then they would see why we get a tad tense when we get issued with taxi instructions when the captain is barking instructions at us (the FO's). (ie really noisy with the props etc )
When I was in Oz I never saw an ATCO on the j/s either (Dash 8).
Pity. I've strolled up and down a few Towers etc in my day. Loved every visit.