Why not Grace?
People just cannot get themselves to agree with the premise that full pardon from God, entrance into heaven, and eternal life have absolutely nothing to do with their behavior whatsoever; that nothing they have done or can or will do in the future has any bearing on whether or not they end up in the kingdom of God (barring, of course, simple faith into Christ).
They cannot get themselves to understand that even a sinful, debased individual, nevertheless justified and covered by the blood of Jesus, can be in God's kingdom.
Deep down inside they believe, in a very real way, that behavior is intrinsically correllated with one's hope of heaven.
How did this happen?
Grace is a naughty word.
If it is true that your eternity can be absolutely secure no matter what your behavior is (past, present, or future), then you can get fire-insurance and live like the devil.
I happen to agree with the last statement. The RCC and Lordship Salvation, and Arminianism would all be on the same page and dissent against grace.
The person who lives like the devil, in RCC, Lordship Calvinism, and Lordship Arminianism, does not go to heaven. Works all have an integral part, one way or another, in one's final entrance into heaven.
The person who lives like the devil (who never the less has eternal life) in FG theology will lose his soul, both in time and for eternity, yet he will be in the kingdom.