Exactly. There are some judges that will rubber stamp warrants without even looking at them closely, but there are still plenty who don't and there's a paper trail as well that provides some protections. When you just go to where no warrant is required, it won't make a difference when the police want to get a specific person, but it will make a big difference on whether they are able to surveil wide swathes of the population and how easy it all is for them.