Someone once told me a definition of a libertarian: a conservative without the moral compass. True or false, your post reminded me of that.
I see them as liberals who like conservative economics, or in a more basic way, children who fantasize, for example “open borders is fine, we merely eliminate all the social programs first, and then fewer people will come”, my answer to them is, first succeed in getting rid of the social programs in America, then we can discuss open borders, just like the left, they want all the bad stuff up front while selling you a bill of goods about a fantasy future.