People everywhere are jerks. I had a father daughter combo repeatedly blowing past me, slowing down to the point I had to go back around them, just to come by me in a dangerous manner again a few weeks back. Not a clue what they were doing, the third time they came past me I let out a few choice words, and thankfully our paths diverged before they slowed to nothing and forced me around them again.

It is the faster traffic's responsibility to yield to slower and pass in a safe manner, that is simply basic laws of movement of almost any vehicles. That applies to cars passing other cars, cars passing bikes, bikes passing other bikes or pedestrians. I don't know what MUPs look like by others, but I know by me, there is usually about a mile stretch where people walk around any given town, followed by long spaces where one rarely sees a pedestrian or slower cyclists that is a burdensome problem to have to slow to avoid.

Or, I have an 8 mile direct shot on a shaded MUP trail with little traffic to where I want to go, or 11-12 miles on a gridlocked rush hour road without cycle lanes, where I will be sitting in traffic in the sun going no where and taking all day to get there.