Serious question: how many times has Apple used a generic patent against their competition? It doesn't seem to happen often, which gives me the impression they're mainly defensive patents.
Unlike with patents if you don't defend a trademark you will lose it. Trademarks and patents are different and I'm curious as to why you're relating them here.
but yes, a trademark is representative of a brand, and it's important for companies to control their brand image, especially companies who are constantly under surveillance by the media like Apple.