As Van Halen and their brown M&Ms have taught us, people tend to skip over the small print. The way to make people actually read things they should, like laundry instructions, is to make them worth the time. Hide a joke inside, and you can change consumer's behavior for the better.
Yeah, some of these might have been designed to go viral, but that ends up being the same thing, don't you think? Maybe now you'll check the tags in your clothes more often. See 25 clothing tags that are worth the time to read them at Geeks Are Sexy.