why are people so negative?

I am going to post now (before I go to sleep) about two events that happened to me tonight. One good and beautiful and the second something troublesome and disturbing.

I will post in the order they occurred, so this one will be about the negative event. The next post will be the better one (and it will be nice to go to sleep after writing about something positive..)
Here goes:

I was on the way home tonight from work on the train. Every day when the train gets to a certain spot, a minyan forms for either Minha (during the summer days when 6:00 PM is still daylight) or Maariv (duing the winter evenings when 6:00 PM is night). I generally do not join in that minyan, as I take the opportunity to read/learn/sleep and I can catch the minyan at other convenient times (either work or at shul at night before my daf yomi shiur). Occassionally I do join in the minyan for various reasons, none of which are too important.

Anyway, tonight I joined the minyan for Maariv. It was an unusually large minyan, maybe 35 or so people. As people are congregating in the "minyan section" getting ready to begin, someone walks in to the group. He raises his voice and he asks loudly (in Hebrew), "Does anybody know if it is actually the time for Maariv?" Nobody responded, so I did. I said not to worry, this is a regular minyan and you can daven in it or not, but the timing is fine. So he says just because it is a regular minyan does not mean it is doing the correct thing.

Now, first of all, this was not a Haredi "fanatic", so do not even suggest that as a rationalization. He was a Dati Leumi regular guy. Second, he stayed and prayed with the minyan despite his objection never being clarified, so his intent was not to not daven and tell people it is wrong, otherwise he would have gone back to his seat, his concerns not being assuaged.

So here is what bothers me. This guy came in to throw a monkey wrench into the works and make people look and feel bad, as if he knows better and is more concerned about doing the right thing. From the halachic aspect itself, it was perfectly ok to daven maariv at that time. It was "choshech mitzrayim" outside. Even if it was not yet Tzais according to all opinions (and I do not know if it was or was not, it is clear in halacha that one can daven maariv from shkia (sunset) on, and under some conditions even from plag Ha'Mincha which is actually during the daytime (a prime example of this being the common early shabbos minyan). So, it is clear that it was a time permitted for davening maariv, at worst one would have to repeat Shema at a later time.

Why did he have to come in and say that and cause people to look down and start shuffling their feet as if to say don't look at me, it's not my fault we are davening now? Does he really think he is better? It is far better than davening shacharis in the morning before netz (sunrise) which he himself does at times (as I see him at times in the shacharis minyan I go to, which sometimes during the late netz days falls out before netz). I would dare say he was not really concerned, as he continued to daven with us.

Why do we have to assume the worst and accuse people of doing the wrong thing? If a group of people, many of whom have the appearance of being knowledgeable in halacha and Torah, have a regular custom to do something which is halachically fine (though maybe not the absolute best way), who is anybody to come in and say they are doing the wrong thing? You don't like, so go away and ignore it, but why attack?

Do we all do this, to certain degrees? Do we each think we are better than the next guy and know more and behave better?

Maybe we should sometimes (read: often) assume poeople know what they are doing and are doing the right thing, and our Jewish community will be far better off.