Dan, not everybody looks as jewish as you do! I am clean shaven and with a baseball cap not regocnized as jew that easy.
Yes, ist has a slight bigger chance, if i have to transfer anyway and can pick between ist and fra and ist is 100 dollars cheaper, i would pick ist. I will not cross the road to the other side of the street, just because on my side there is a tree and there is a bigger risk of it falling on my head if i walk on my side of the street.
You can never travel risk free... Take a boat, as a plane could crash
I was in ist and dxb and had no issues at all. Had a client, that davened in the ek lounge in dubai a few weeks ago with talis and tefilin.