"I build a house without a contract. If you like my house and want it you have to pay me for it."
*If* I want the house. Nobody owes you nothing just for having built the house.
"Patents are just a bank for your ideas."
Unluckily, no, it's not "just" a bank for your ideas. On one hand, no, patents never have been about ideas, but about implementations. On the other hand, somehow you have an upper hand even if I reach to the same implementation by myself.
"Otherwise all the smart people that come up with ideas have to spend the majority of their time marketing/finding buyers"
You see? just like any other company out there. "Oh! but I don't wanna spend my time marketing/finding buyers!". Well, that's what being salaried is about.
"Patents, when granted to things that are non-obvious/prior art etc, can be a huge time saver freeing up the creatives to continue to innovate"
Hirings, when granted to [engineers, beancounters, clerks...] can be a huge time saver freeing up the engineers, beancounters, clerks... to continue to go with their engineering, beancounting, clerking...