Older, and slightly More Flammable: Thank You Therma-Care Heat Wraps

I like to read warning labels and fine print on boxes. The things they are required to print on them these days cracks me up. Like nut warnings on packages of nuts. Today I was reading the Therma Care Heat Wraps box. (Shameless product pitch - if you have not tried them for cramps and aches, you are missing out. They're like ski boot warmie packs but with velcro to wrap around you and make you feel soothing heated love)
On the back of the box it reads:
55 OR OLDER: YOUR RISK OF BURNING INCREASES AS YOU AGE. IF YOU ARE 55 YEARS OF AGE OR OLDER, WEAR THERMACARE OVER A LAYER OF CLOTHING, NOT DIRECTLY AGAINST YOUR SKIN...

I was not at all aware of this. But apparently, we are all getting slightly more flammable with age.