I would say many but not most. There's plenty of Muslim shop owners. There just not Jihadis. After Bush opened the floodgates to Muslim immigration post 9/11, many came here simply for a chance to prosper.
There's a Muslim gas station owner by my house. I stop by after work every night to pick up a couple of 4-Lokos. He's a good guy. Calls me "boss". Has no problem selling me alcohol. Then again, I'm white so I'm not really a threat unlike the black youth who shoplift (and are the reason he spent a great amount of profit installing a bulletproof plexi-glass barrier).
4-Lokos...Dear God why?