How many times do you pull your spark plugs (for reading, or for cleaning, etc.) before you worry about the spark plug seals not sealing anymore? Is this even an issue?

My 2$ NGK spark plugs are no longer available and the replacement is 8$ each now. I want to reset the gap but I am first curious about the above. If I can keep pulling my cheapies out then I will, but I am not sure if the spark plug seals are good over and over again.

Thanks