The radical Islamic terrorist is carrying out acts against an entire population in the name of Islamic fundamentalism. He is obviously more dangerous of the two.
The consequences and repercussions are obviously greater and more serious then your dime-store robber. 
And attacking your own people to support our enemy (ISIL and any other radical Islamic terrorist group) is clearly not on the same plain as attacking people in a convenience store for your own gain. 
The terrorist is a trader to his own people and should not be lumped in with a common criminal. That's simply not acknowledging the serious problem of radical Islam and pretending it's not about the religion, when it certainly is.