Yes! Of the three entirely different things often lumped together as "Intellectual property" trademark is the one which has the best claim to actual social value where the thing we're giving up (can't use protected marks for things, e.g. I don't get to bottle whatever brown sweet liquid I made and call that "Coca-Cola") is a fair trade for what we're getting (able to associate product qualities to marks, e.g. I know I like Cherry Pepsi Max better than any type of Cherry Coke)
Is it a fair trade in this specific instance? You also can't, apparently, have coffee in a cup that's too close to the Coca-Cola shade of red. Does that help you know that your coffee isn't coke?
If we can start with the concept of trademarks being valid - they protect people as much as the company, it then comes down to whether a given product would mislead the typical consumer. If you run a nightclub called "M-C Donald's" then nobody is going to think it's a crappy burger joint. on the other hand if you use similar colors and/or font that mcdonalds an impartial person might think you're trying to trade on Ronald's name and mislead your public.
On the other hand if oyu run a hair salon called "British Hairways" with similar colors to the airline [0], I don't think a reasonable person would link the two.
There are of course going to be edge cases where people disagree. If you're making a red coffee cup that should be fine. If you're making it red with a swirly "Coffee" font which looks similar to the swirly Cocacola font that's probably not.
