This would imply that God can be 'bought.' If that's how the Protestants understand God's integrity, it would be the ultimate in anthropomorphism.
It's not a gift one gets for a birthday or at graduation. It has no chance of being corrupt by the Giver. It is priceless (nothing in the world can buy it, earn it, deserve it). There is no need whatsoever to call it free, or a gift. In fact, it's just plain wrong and misleading.
"It is priceless (nothing in the world can buy it, earn it, deserve it)."
What then is this "grace"? Is it the salvation wrought by the finished work of Christ on the cross?
Uh, no, just the opposite. We're making the point that because something is free, it cannot be bought.
There is no need whatsoever to call it free, or a gift. In fact, it's just plain wrong and misleading.
God's grace is the predestined mercy He has chosen to bestow upon some men through the sacrifice of His Son. If you think it is wrong to call grace a "gift," then your argument is, again, with Paul.
"For by grace are ye saved through faith; and that not of yourselves: it is the gift of God: Not of works, lest any man should boast." -- Ephesians 2:8-9