I heard the advice that you shouldn't click if you don't follow up with a treat - at least if you want the click to remain effective reinforcement. As I understand it, the point of clicking is that it acts as a virtual and instant treat that can be given at the exact instant the desirable behavior is done, while giving a physical treat takes a moment to do making it harder for the cat to understand what behavior they did that caused it - kind of like time shifting the dopamine hit of receiving a treat backwards in time to more tightly couple it with the desirable behavior. So my strategy is to only click if I have treats on hand, but then I use that to train commands that don't always result in a treat or only result in praise. That way the click->treat association remains strong and useful for training new behavior but I end up with commands I can use without treats or weakening the usefulness of the clicker.

That said if it works for you then it works! I just read a lot of content about animal training so I nerd out a bit.