At an established company, yes, that's a reasonable salary for a developer.
But when you're starting a startup, you don't take a salary of that size. You live cheaply and take only the minimum that you need as you commit yourself to building your company. It's not a life for everyone, but it is the startup life.
Sounds like anyone with a family is pretty much excluded from what you call "startup life" then. $80k wouldn't get me alone through half a year without selling my house and moving somewhere really cheap in the US.
But when you're starting a startup, you don't take a salary of that size. You live cheaply and take only the minimum that you need as you commit yourself to building your company. It's not a life for everyone, but it is the startup life.