I think there are two questions here.
The first one is SHOULD teachers perform gate guard duty. I will not give an opinion as this question is very subjective in nature and would appear the answer can be influenced by many contextual factors (size of the school, organizational culture, experience and level of responsibility of the individual teacher, etc.…).
The second question is whether refusing to do gate duty, which can be perceived as being confrontational, contrary, disrespectful of the school’s management, insensitive to local culture and indifferent to the success of the school or organization, will be helpful in achieving your individual career goals or make your life happier.
I have a pretty strong opinion on this second question.
I am not sure holding onto the 1950s union attitude of the “management” as the enemy helps to become successful in the ESL or any other industry.
Ironically, while typing this I am overhearing a conversation by an employee who always refuses to engage in any “extra” activities complain about his low performance evaluation. There is a correlation between his refusal to do extra work and his poor performance appraisal, but of course it could just be a coincidence and the two activities are unrelated, or maybe the two could be related.
Oh well, we all have to make our own choices and live with the choices we make. If you think refusing to stand gate guard duty when it is expected will help you live a happier and more successful life, by all means refuse. If you think gate guard duty is a slight inconvenience but will help you achieve bigger and more important goals, go ahead and do it.
In my experience, the angriest and most insistent individuals who claim the decisions they made were absolutely right and everyone who disagrees with their attitudes is wrong, are likely the individuals the least satisfied with the results of their previously made choices.
Since I am not expected to stand gate guard duty, I don't have to make the choice.