I am shy and usually don't advertise to pple about my running. Despite this, I have had a number of experiences when pple discourage me from running marathons.
1. My career counselor told me I should include a hobby in grad school apps, because they want to know I do not study 24/7 and have outside interests to keep me sane.
I told him I enjoyed running. He said in a tone of irritation "Let me guess. You run marathons?" I nodded, and he said "Well, they will not care much for that. They want to see something that shows creativity and personality, not mindless monotony."
I thought it was so harsh, and his tone made me feel like I said something offensively inappropriate.
2. One of my friends told a coworker (they only met once, and my friend just talks a lot) that I run marathons. A few days later, my coworker randomly commented on the title of a marathon article on Yahoo! that marathon runners need to "get a life and find something better to do."
I could not help but think it was mean-spirited as I was one of the only people in earshot.
3. I was considering doing a mud run... until I saw their statement of purpose. You can check it out here:
Apparently, their number one "about us" is:
"And the only thing more boring than doing a marathon is watching a marathon. Road-running may give you a healthy set of lungs, but will leave you with as much upper body strength as Keira Knightley. At Tough Mudder, we want to test your all-around mettle, not just your ability to run in a straight line, on your own, for hours on end, getting bored out of your mind. Our obstacle courses are designed by British Special Forces to test you in every way and are meant only for truly exceptional all-around people, not for people who have enough time and money to train their knees to run 26 miles."
I could list more but have already written way too much...