Interesting analogy Ali, and I understand your point, but my take on it would be a little different.
What if the two boys were raised without a father and only told stories about him. Imagine the two boys are raised to believe that their father is actually an extremely wealthy man who, when the time is right, is going to come back into their lives and give them all his money, but only on the condition that they do good things and that they worship him.
Now, the boys have no proof of this other than what they are told, so one boy believes in this father and the other one does not. The first boy does good things in the hope of gaining wealth, while the other boy is just as good, but not in order to gain the wealth. The second son does not disrespect the father, he simply does not believe he exists.
Now, does the father really exist? Who knows. If he does why does the father feel the need to have his children worship him as a condition for the reward? If the father truly loves the children would he really feel the need to punish one of the sons (despite his good deeds) simply because he did not worship his father?
Firstly, GranPa Woodrow said it right when he said that Allah is independent of all needs.
Coming to you Brother, just look around and you'll see proves everywhere of his existence, you may find not find them convincing though and that's a totally different question. The trees, the mountains, the animals and all that includes nature are proofs of His creation. The absolute symmetry and balance in nature on our dear earth cannot be a result of an accident called the big bang. There definitely is an architect behind all this. It all takes us back to the previous question of what one would consider as a proof or "that bright discovery of faith."
And the analogy, the father just does not show himself to his children, that's the only thing which is missing in this love. Apart from physically coming in front of his kids, the father does each and everything required of him for the good upbringing of those 2 sons. Just like any other father, he wants his children to prosper.
I'd go straight with "Allah" here rather than the example. Allah is the one who sends us sustenance. If He wishes He can hit any part of the world with any kind of disaster like a drought, flood, earthquake etc. Now, Allah does not require anything from us, not even worship. If all the theists in the world, give up their religions and just start having independent lives, its gonna make absolutely zero difference to Allah. He'll remain to be as supreme as ever. He is not a worldly king who needs a kingdom to be called The King. Allah was Allah even before the creation of the heavens and earth and He still had those 99 attributes which are mentioned in the Qur'an and He'll remain the same forever. What we're having a debate over here is about being a good person with/without faith whereas Allah is way above all of us. Just have a look at his attributes in
this link. We humans can strive and become good or better but Allah is the best. We're just comparative, He's superlative. The point that I'm trying to stress is His decree of punishment for the unbelievers. Among His attributes are
Al-'Adl and
Al-Muqsit which mean "The Just." He has decreed the punishment for unbelievers because He's Just and there has to be a difference between those who are thankful to Him for His never-ending blessings and those who are not. Punishing any of us is not gonna increase or decrease His honour. As He states in the following verse:
What can Allah gain by your punishment, if ye are grateful and ye believe?
Surah An-Nisa - 4:147
What I've observed in many people (including some Muslims) is that they think that Allah is a tyrant (Nauzbillah) who has simply imposed His worship on humans which is absolutely not true. If He were a tyrant then He would have seized every wrong-doer right by the throat at the time he's committing sin. Rather he's
Al-Ghaffaar, The One who forgives the sins of His slaves time and time again and keeps giving second chances to His slaves. We worship Him not solely because He has asked us to but because He deserves it. No matter how major a deed of humanity we do, we'll never be able to compensate to His blessings or show us our gratitude.
Prophet David (PBUH) once asked Allah to show him His blessings and Allah said "breathe."
Every breath that we take is a blessing from Allah.
Brother, the proofs are everywhere and
the matter of reward/punishment is secondary. Primarily, its just about being thankful to HIM and gratitude is a major issue (which atheists lack making them miss out on the COMPLETE goodness).