This isn’t for admission, but for a scholarship. Take Alabama. They have a requirement for a 3.5 gpa. They do not question the gpa submitted by the high school, if it has honors on it, if it is from a home schooler, if it includes non-core classes. The gpa is the gpa and however the high school calculates it is fine. Send in your best one for the scholarship and they’ll take it. Other schools might make adjustments or only accept the unweighted gpa or only core classes. It’s up to the college.
It may not be fair. It is the school’s choice. Admissions is different.