Information you expose to the public internet, behind an isp or not, is not private or secure.
This is like complaining that people keep taking walks by your house whenever your wife sunbathes nude on your front porch. The people doing the looking aren't the problem. Where your wife is exposing anything sensitive is the problem.
The solution is to move your wife to the privacy of the back yard, buy her a sunbooth,or accept that she's on display to the public.
Much the same, make sure your firewall facing your public network connection only exposes what you want it to. Part of the implicit structure of the internet is that by connecting, you're agreeing to be connected to, to be visible to everyone else that's connected.
Leave Shodan be, their presence is important and relevant to the ongoing discussions of educating the public and maintaining accountability for security decisions by giant corporations.