My local parkrun is 2/3rds on concrete, 1/3rd on trail.... the trail/grass section is hilly and muddy enough that unless in dry conditions i would wear fell shoes.

On New Year's Day i went down clad in my Mudtalons, due to the torrential rain, only to find it had been cancelled.... still ran the course, but was now free to simply do the concrete section for 5km..... meaning i did a 5km tempo, followed by an 800mtr rep, all on the concrete, in fell shoes...

I don't think it should be something that someone with conditioned legs can't handle once in a while, but i still wouldn't want to do it very often.