Why does a custom rpm not being installed because of the conflicts from filesystem rpm?

Issue

• The same build process that used for Red Hat Enterprise Linux 5 & 6 works for most RPMs but fails to install on Red Hat Enterprise Linux 7 for one which has files in a number of system locations

# rpm -i /local/compile/RPMS/x86_64/customtest-7.6.0.1-1.el7.x86_64.rpm
        file / from install of customtest-7.6.0.1-1.el7.x86_64 conflicts with file from package filesystem-3.2-18.el7.x86_64
        file /etc from install of customtest-7.6.0.1-1.el7.x86_64 conflicts with file from package filesystem-3.2-18.el7.x86_64
        file /opt from install of customtest-7.6.0.1-1.el7.x86_64 conflicts with file from package filesystem-3.2-18.el7.x86_64
        file /var/log from install of customtest-7.6.0.1-1.el7.x86_64 conflicts with file from package filesystem-3.2-18.el7.x86_64
        file /usr from install of customtest-7.6.0.1-1.el7.x86_64 conflicts with file from package filesystem-3.2-18.el7.x86_64
        file /var from install of customtest-7.6.0.1-1.el7.x86_64 conflicts with file from package filesystem-3.2-18.el7.x86_64
        file /etc/rc.d from install of customtest-7.6.0.1-1.el7.x86_64 conflicts with file from package chkconfig-1.3.61-4.el7.x86_64
        file /etc/rc.d/init.d from install of customtest-7.6.0.1-1.el7.x86_64 conflicts with file from package chkconfig-1.3.61-4.el7.x86_64
        file /etc/rc.d from install of customtest-7.6.0.1-1.el7.x86_64 conflicts with file from package initscripts-9.49.24-1.el7.x86_64
        file /etc/rc.d/init.d from install of customtest-7.6.0.1-1.el7.x86_64 conflicts with file from package initscripts-9.49.24-1.el7.x86_64
        file /etc from install of customtest-7.6.0.1-1.el7.x86_64 conflicts with file from package yum-3.4.3-125.el7.noarch
        file /etc/rc.d from install of customtest-7.6.0.1-1.el7.x86_64 conflicts with file from package yum-3.4.3-125.el7.noarch
        file /etc/rc.d/init.d from install of customtest-7.6.0.1-1.el7.x86_64 conflicts with file from package yum-3.4.3-125.el7.noarch

• The same SPEC file on Red Hat Enterprise Linux 5 & 6 generates an RPM that is installed via rpm/yum