To play Devil's Advocate here and in an attempt to be fair;...courts of initial appearance try to escape ever having to rule on Constitutional issues by declaring that such arguments are reserved for appellate courts. The first court you appear in or are tried in will claim they are there only to determine if the laws have been broken, NOT whether the laws are in fact legal. With this as their premise is why you will often hear such statements as described by the OP,...although usually the judge puts it a bit more delicately.
Now in fact, there is truly nothing PREVENTING any judge in any court from considering and ruling upon Constitutional argument, matter, motions or principles brought forth. But neither are they REQUIRED to in that initial stage by their superiors higher up in the judiciary. Thus is provided every judge the cop-out they need to act on their particular bias in cases before them. If the judge is sympathetic to the party bringing forth the Constitutional matter, they can declare the supremacy of the Constitution and that it bears on the case and render accordingly. But if they are hostile to the party bringing up a Constitutional principle, they can simply dodge responsibility by claiming such is the exclusive realm of the appeals court and that it should be addressed there.
