In 11 trips, river cruise, small ship cruise, land tours, we, too, have had young people teens to mid 50's on some of these tours, from the 80+ grandmother with a 22 year old granddaughter, to the doctor and family with middle age children with some of their grandchildren, parties of 6 or 7 family members. These age groups have not been on most of our trips, only on a few of the trips.
My enjoyment of a trip is quickly lost if the program director is not sensitive to the seniors who have hearing loss, who, with hearing aids still cannot make out what the PD or local guide is saying if they speak in soft tones, soft high pitched tones, and move their head away from the whisper mic. And, I also don't feel comfortable with PD;s who are first off the bus and immediately start walking while not waiting for the bus to empty out. It takes time for the first passenger to pick up their purses/cameras, step down slowly the first step, turn to get to the deeper step, then the last step, and on to the street/curb. By this time the people behind are ready but can't move forward (or down the back door steps) until the first passengers are down. By this time a PD is half a block away, wondering why we are so slow. That is what the first poster is discussing. And I agree with the poster.. Just my view, too.
I'd like to add this quote from: GCT>Community>People and Culture:
"For many years, Grand Circle Travel was based in New York City where it served members of AARP until 1982 (Grand Circle Travel now serves all mature Americans). "
Having said all this, I have enjoyed all our PD's except one, and they have all been more than excellent except the one.