One day I attended a minchah minyan of a kollel (in Eretz Yisroel), and was quite shocked to see that they did a heicha kedusha. Since it was minchah gedolah, there was no chance of them overstepping shekiyah. Being a kollel minyan I sincerely hope that at least nine of those present would have answered amen to the berachos. The minyan was followed by the afternoon break and so one could not give the answer “bitul Torah”. The answer that Chazal did not institute the repetition of the amidah for people like kollelniks, which even if acceptable, is based on the assumption that no people living in the area or those passing  by at the time attend the minyan, which is often not the case.