Why do so many people play 3...Bg4 in the Philidor when everybody knows it's bad

Even high-rated players do it! Why?????

because they don't know the opera house game

Excuse me, what was the first game you ever saw in you life?

That game.

Same answer from the who;e chess community.

Are you talking about this horrible line, by any chance?

Ah, yes, that line. Well, the people who play Bg4 mostly play Bxf3.

Typically the people playing Bg4 don't have any tricky continuation in their mind either, that's why it sucks so badly. As Fiveofswords, I believe Bg4 can be played, if you are willing to give up something for some activity

Because people are stupid.   

I meant patzers of about 1800 strenght.

Either because your playing bullet chess, their inexperienced, or their frustrated online.

I am playing online chess

frustrated online?

What do you mean?

Maybe he posted White's effective counter to the ..Nd7 gambit, but he took it away because he didn't want to reward you for spamming the thread!!!!

I only see it from really weak players who get a lost position before move 10.

I didn't know reasonable players try it form time to time.