Going to church doesn't give you permission to be a meanie. It doesn't wipe the slate clean so you can be nasty in good conscience.
How we act every day is what matters. Every moment is an opportunity to practice our faith ... by being kind, showing patience or stopping ourselves from saying a hurtful remark. Love for God IS in the small stuff.
A day of worship provides a positive action plan; the rest of the week is the follow-through. And Saint Peter's keeping score.