Amen. If in doubt, leave it out! For me, a "gray area" is something I'm not totally sure about, and so until I'm convicted one way or another, I put it on hold. By so doing I believe and feel like I am avoiding the shadow or reflection of sin, and the appearance of evil.

For example, there was a time when I wasn't sure about owning a bicycle or bowling, due to plain statements made by Ellen White. It was a gray area for me and so I put it on hold. But after having studied the question, I am now (have been for years) comfortable with owning a bike and going out bowling with friends.

Is sinning unwittingly and gray areas the same thing? Are we abstaining from the appearance of evil if we avoid so called gray areas? Or is there more to it?

The following examples from Ellen White indicates that abstaining from all appearance of evil involves at least avoiding practices or behaviours that can be construed by others as questionable or misleading.

Temperance, page 98, paragraph 2
"I do not see how our brethren can abstain from all appearance of evil and engage largely in the business of hop raising, knowing to what use the hops are put."

Supplement to the Christian Experience and Views of Ellen G. White, page 38, paragraph 1
"In 2 Thess. v, 26, Paul says:--"Greet all the brethren with an holy kiss." And in the same chapter he says:-- "Abstain from all appearance of evil." Verse 22. There can be no appearance of evil when the holy kiss is given at a proper time and place."

General Conference Daily Bulletin, February 6, 1893, paragraph 5
"There should be connected with the mission married persons who will conduct themselves with the strictest propriety. But the danger is not alone from youth, but from married men and women; workers must build up the walls of modesty and virtue about themselves, so that women will not allure men, and men will not allure women, from strict propriety. 'Abstain from even the very appearance of evil.'

Testimonies for the Church Volume Two, page 248, paragraph 1
"You have fallen into the sad error which is so prevalent in this degenerate age, especially with women. You are too fond of the other sex. You love their society; your attention to them is flattering, and you encourage, or permit, a familiarity which does not always accord with the exhortation of the apostle, to "abstain from all appearance of evil."