You must live somewhere warm. On Canadian highways 15 mph is just a fact of life a few times a year. I've never seen a Canadian highway with a minimum speed.
Of course! I did not mean that anyone should ever drive any speed that is too slow for given conditions, I have driven 5-10mph on higways with minimum speed of 45+mph during inclement weather.
I live in the USA and can tell you with 100% certainty that if I drove 15mph on a highway drivers that pass me will call 911 and I will be pulled over. driving 30-40mph over the limit is unlikely to trigger the same concern from other drivers unless I am “street racing”
other cars or driving erradicaly