You want to know the secret? The secret is to find good hotels and stay there often.
You don't make relationships with hotels. You make them with people.
The best hotel I've ever stayed at is the Kimpton Gray in Chicago. I had a great stay where I met the bartenders and front desk staff and sent the GM an email telling him about my stay. And that began the beginning of an incredible friendship. I got upgraded all the time. I had booze in my room when I arrived. When I said I loved White Castle, the concierge put a microwave in my room and bought the frozen cheeseburgers and put them in the fridge in the room. And I bought them cheesecakes and an Edible Arrangements. Not because I owed them, but because I wanted to. Because we liked each other.
So until I find another experience like that, then I'll accept the "loyalty" from the major chains, and continue to be really nice to people.