You can if you have command on the language (Arabic) because when you wear the Thob n Akhaal n Gutra with Kahfia then no one from the locals and arabs will talk english with you... specially the traffic police...one can end up in more problems .....

Secondly, it should be proper as per the Qatari style...note that the same white and head gear with some difference of stiching and color/prints can have the style from any other GCC country...though it does not matter much...but just indicating as you desire to wear a QATARI dress...

By the way the face does matter as well, and further more, most of the locals are not shaving the beard and or moushtaches...