You can factor the vUris.empty() out from the loop, even skip the loop if there are any URLs. You still need the loop to check for switch characters, but the Uris check has already been done, so

    if(vUris.empty())
    {
        bool fCommandLine = false;
        for (int i = 1; i < argc; ++i)
            if (!IsSwitchChar(argv[i][0])
                fCommandLine = true;
        if(fCommandLine) 
        {
            ...
        }
    }