Well, I certainly do that in order to discern the plausibility of a theory.
One can certainly ask whether a theory is well-supported by evidence (which takes different forms depending upon the field). But the question you asked should be reversed in two ways. First, one is better served asking what ways pseudoscience uses (what appear to be) elements and methods of the scientific endeavor. Second, one asks not so much what elements or methods from the sciences are actually used in pseudoscience, but rather how pseudoscience attempts to appear to use these elements and methods in order to appear scientific whilst actually deliberately misusing established methods and relying upon a variety of other schemes to appear scientific in order to bolster claims and the manner in which they were "established".
There is all the difference in the world between things like bad science or metaphysics masquerading as empirically-grounded theoretical physics on the one hand, and pseudoscience on the other. For example, I regard most of the "research" in so-called string theories at best mathematical research and at worst extremely poor attempts to make leaps from unfounded
formal assumptions (that are assumed because of their similarity to a more general framework in more established but still speculative physics, and also assumed rather than postulated because the mathematics that it would take for such postulates to be well-formulated doesn't exist yet) to theories that often cannot even in principle make contact empirical findings (except via the assumption of existing theories to which they add nothing but nonetheless claim to "predict" in the same way that e.g., most string theories "predict" supersymmetry because they depend upon it to work at all).
Likewise, there is outright fraud in the sciences, there are entire fields that rely heavily on a very troublesome statistical inference framework that is in no small part a cause of various replication/reproducibility crises across certain sciences, and more.
Some work in some of these might qualify as pseudoscience, but for the most part this term is better reserved for "research" that attempts to mimic actual scientific practices and principles, usually for the sake of a non-scientific audience who cannot adequately judge the results, in order to lend credence not just to their claimed results but to the nature of their inquiry.
As an example, one need only watch shows about hunting ghosts or paranormal investigations more generally. The general nature of pseudoscience, as opposed to the larger category of bad research, is that the appeal to scientific veneer is generally not much more sincere than a stage magician showing you that that the box is empty and there is no possible means of escape. It is an illusion. So, for example, a common trick is for some alternative hypothesis is proposed in order for it to be rejected an by this sleight-of-hand it is claimed that the only remaining answer must be the "default" hypothesis, i.e., a ghost or spiritual presence.
It is true that the demarcation problem has a lot of gray areas and that the delineation between pseudoscience on the one hand and bad research, research that isn't scientific but philosophical or metaphysical or mathematical or historical, fraud, and so forth on the other hand can be a murky one.
It is also true that looking at pseudoscience in order to understand how it is pseudoscience, as Sabine Hossenfelder does (and many others have as well) is instructive and important- it was a central goal of Popper's notions of falsifiability, for example).
But to ask what scientific fields contain elements of a practice
defined in a large part by the use and misuse of scientific methods and elements is a waste of time. Pseudoscience isn't even pseudoscience if it doesn't contain at least some elements and methods from the sciences, and therefore all sciences by definition contain elements in common with pseudosciences (simply because on is an attempt to appear like the other).
If scientists uncritically invent add hoc ideas (for instants "dark matter") to former assumptions, all red warning lights are blinking in my mind.
Yes, but you don't really have much of an understanding of the nature of physics or cosmology or how evidence in either field is tested, but rather prefer to adopt a pseudoscientific approach to a would-be cosmology that uses terms from legitimate physics to appear to be scientific to non-physicists in ways that convince only non-physicists or others who are misled by claims about electromagnetism that don't even begin to address the ways in which E&M breaks down as more than an approximation made by those asserting it to be the explanation behind various phenomena shown in youtube clips.
