Actually a lot of companies do get upset and spend a lot of money protecting their trademarks. In the early 1960s my first job on leaving college was with the Caterpillar Tractor Company and part of my product familiarisation was reading all the trade magazines, noting all the use of the word caterpillar with a small c as a description of a crawler tractor or track . The authors / publishers were then sent a snotty letter pointing out the error of their ways.
When I created my former company's web site I used the word Strimmer and even though acknowledging that it was B&D's trade mark I received a three page letter demanding that it was removed immediately - or else!!
Now, where's my Biro - sorry, ball point.