They have a poor/low view of Afghans, Pakistanis and Arabs, the men in these ethnicities, style their beards in a similar fashion and are easily discernable.
Skin tone is a big give away, they can spot the difference between the slight tinge of shades, Germans aren't big on racism towards blacks, racist Germans are mostly just anti - 'arab' / islamophobes.
You must also take into consideration that there never really have been any large scale Terrorist attacks perpetrated abroad by Bangladeshi nationals.
We have a reputation for being rather meek and docile, our true face comes out only when we are dealing with other Bangladeshis, usually involves cheating our countrymen and/or ripping them off.
To be honest, we don't have any reputation abroad, good or bad whatsoever.
Most Germans I've spoke to are fascinated when I tell them, a Muslim majority country like Bangladesh exist with a female premier and a secular constitution.
And then they usually say something along the lines of "Right, I've seen made in Bangladesh tags in clothing stores but never paid much attention".
Anyway I just give the racist mongrels a wide berth and pray sincerely that some bangali fanatic doesn't carry out a Terrorist attack and make us all a target of unjust discrimination.
A good tip when dealing with German racists, is to reply back in German, usually when they rant they assume you don't speak German, when they find out you do, they get flustered and often just quiet down.
Even better if you have ethnic German friends with you, they will never ever even target you, for they don't want other Germans to see their 'racist' side.
Personal image is a big deal in Germany, even among racist mongrels.
Avoid East Germany, especially Saxony and it's cities like the plague.
Big beards and speaking or using Arabic words like 'Inshallah' will also increase your chances of attracting skin heads.
Been to Italy, the tourist industry is big there, especially up north, so they keep their snide remarks to themselves.
Anyway, don't let all this deter you, Germany is beautiful country with a unique culture. The racists are far and few in number, the youth are very very open and understanding of other cultures, women especially as always are less racist.