Just like Ford or BMW will give you a discounted or a free car if yours is stolen, right?
There is no "they" with androids. A huge range of manufacturers make phones that run that OS and I'm pretty sure none of them gave you a free phone. What might have happened is the carrier or Phone Network company may have done. Lost or Stolen phones are the same as lost or stolen cars, televisions or anything else - a matter for your local police.
Apple provide a range of services - up to and including disabling the device permanently. But the notion that Apple would accept your word that it's your phone simply because you have a serial number and a receipt is daft. There are hundreds of ways you could come into possession of that data. Apple - like Ford or BMW - have no way of knowing if you got them legitimately or not, so there's no way they'll deal with you. If Law Enforcement - who do have the means of verifying your story - make a legal approach to them, that would be a different matter.
How hard is it yo put inof into a database and tell me the last known location.
Sure, but how hard is it for Apple to know that you are a legitimate person with a lost phone and not, for instance, an abusive partner searching out a fleeing victim to harm them? That's why this is a matter for the police and not Apple.