Is it rude to bring your own food in Polaris?

I usually bring my own food on United since I’m not a fan of the onboard meals. Did the same on a recent IAD–GVA Polaris flight (Potbelly turkey sub, extra hot peppers) and got some side-eye from the crew when I skipped dinner service. Didn’t think it was a big deal, but now I’m wondering is that frowned upon in business class?