If you went to an army ceremony, it would also be hard to pick people out due to the uniformity (pun intended) of the dress. Is that also objectionable?
There is an appropriate way to dress for each occupation.
In a business setting, you will likely find the same dark suits, etc.
While there is room for some variety in many professions, a (married/Kollel) Ben Torah, lihavdil, should look at least as professional as a business man, and this is probably what you saw in Lakewood.
As far as the raincoat, I only know of one that covers the felt hats that Bnei Torah wear, so that would explain the uniformity of that choice.