The analogy puts things a little to starkly, but it does look as though conservatives are practical libertarians and libertarians are impractical and utopian conservatives. Conservatives value liberty and seek to increase it, but recognize that there are limits to how much freedom and how little government we can have. Libertarians seem to be demanding the absolute and the perfect in the all to imperfect here and now.
Of course the closeness of libertarians and conservatives is a result of the times and the growth of socialist, social democratic, welfarist and regulatory ideologies. In the 18th century, libertarians were radicals and revolutionaries, and what conservatives wanted to conserve was, to a large degree, social hierarchy, state power and paternalism.
Things have changed much since then. Universal suffrage, socialist ideas, bureaucratization, and the development of the media have transformed the role of government and shifted the political spectrum. Free markets have come almost to be seen as the status quo, in spite of their massive transformational power, because governments have made even more sweeping and malign changes.
Conservatives and libertarians need each other today. On occasion, each will be able to make other alliances, but a permanent falling out would mean letting the socialists win.
So long as conservatives and libertarians concentrate on what is actually likely to be achieved in politics their interests will largely coincide. The recent explosion in the media, though, has created markets for radical or distinctive niche views, that have more to do with creating or expressing individuality, rather than with effectively organizing for practical and necessary political action.
It may only seem that way. I know thousands of libertarians and I never met ONE who demanded what you claim seem to think.
We want things to turn around. We want to be going in the right direction, notwithstanding our ultimate ideal situation.