I've had many free grace pastors, and not one made obeying Christ "optional."
Rather, they admitted the downright difficulty of it, admitted many folks fail at it, and urged us to continually commit to obedience. God would empower us to better obey if we did.
Never heard a free gracer tell anyone they could come to Christ for salvation, holding onto their sins.
Rather, they teach you can come to Christ for salvation while sin still has a hold on you.
Here is a thought. Do we come to Christ and or God for salvation or did God come to us through Christ born a man child, died a man child and was resurrected a man child, with salvation?
Let God be God.