You may have done all of those things, but that doesn't make those things your job. While the action of the tech in this case was something I'd never do (though mostly as I wouldn't want the consequences), I would have politely told them that no, it is not my responsibility to fix your lamp and I don't have the spare time to do so anyway. Had they asked me when I wasn't doing something related to my job and had they asked politely, I would have helped happily.
If I am the generally helpful person who does what everyone wants and because of that, I don't get my actual job done, management isn't going to care that I'm useful to my colleagues. They are going to complain about why the stuff they wanted isn't there, and I am going to face consequences. I will therefore not interrupt the important responsibilities of my job for people who demand my time without reason. I'm entirely on board with being helpful if I can do so without compromising that, but at some point, this is a thing I do by choice and therefore I may choose not to when circumstances are different.
Biting the hand that feeds IT
