I think the EM field properties are somewhat peculiar even before you get to experimental results that force you to quantize the field. Granted, the EM field is not so weird that understanding the general properties of more tangible waves isn't helpful. E.g., I learned a lot from the ripple tank experiments and demonstrations in my high school physics classes, demonstrating properties like diffraction and the tendency not to scatter from too-small obstacles. That kind of stuff applies nicely to EM waves. But that general familiarity with waviness didn't prepare me for things like relativistic invariance. And historically, I'm in good company there: various sharp 19th century physicists were misled about EM by pursuing the analogy with the more tangible waves they were familiar with.