Oh please! As if As if a Chassidish guy dressed in his Chassidish garb from head to toe wouldnt get stares in a modern orthodox shul! Would anyone go over to him? Would people wonder whats HE doing HERE? How many people would say hello and ask him if he needs a Seuda?
Lets face it, all of our communities need to work on being more accepting and less judgmental. However since we are all just Yechidim the only thing we can do is change OURSELVES. If enough Yechidim change themselves it will rub off on everyone else and every community as a whole will have a greater sensitivity of Ahavas Yisroel and Hachnosas Ohrchim.