A popular preacher once said when the purpose of something is unknown, abuse is inevitable. One Sunday morning my pastor gave an interesting illustration. He collected a phone from someone in the congregation and asked us if the device was meant for making calls, which is obviously true. He also asked us if it's possible to used that same device as a spoon for eating food, which is true also. But just because we can use the phone to take out food from a plate and eat does not mean it was meant for that purpose.
This is a scenario of abuse of purpose. Just because we have the ability to do certain things and live in a certain way does not mean that is our purpose. Knowing the purpose for existence is a knowledge that we should prioritize knowing above every other thing. We are God's masterpiece. Just like every inventor has a purpose for that which he events, God likewise has a purpose for creating us.
Ephesians 2:10 - For we are his workmanship, created in Christ Jesus unto good works, which God hath before ordained that we should walk in them.
Our existence should be pleasing to God. No inventor would be disappointed if He sees his invention functioning in accordance to what he had in mind when creating it. It once repented God that He made man because man wasn't living out the purpose for which He made him. We should maintain a life evident of good works.
Our purpose on earth is to please the father who is our creator