cinderella-
Without discussing your specific example (because I don’t think that it was your point), here’s what I think. Hashem gives us Shabbos for a reason, and He tells us the reason in the Torah. He wants us to acknowledge that he created the world and that he runs it. How does he get us to acknowledge that? By giving us a day of rest [on the seventh day of creation]. The restrictions have a reason, they are to insure that we become mindful of the fact that we are specifically resting and not just bored. When we figure out all the technical details and find the “loopholes” not only is it not against the spirit of the law, it’s exactly the spirit of the law! Because doing so keeps us mindful of the fact that there’s something going on that we should think about. If we were to say just be machmir on everything you would have a bunch of people sitting on the couch all day, but now that there is room for “loopholes” you have everyone discussing maybe this is okay because of this and this reason etc. and you end up with everyone being very cognizant of the fact that it is Shabbos, and people start thinking hey what’s Shabbos all about anyway, and they remember what Hashem wanted us to remember in the first place.