Not really... Parkrun best of around 18:30, and did a track mile in about 5:20 a few weeks ago... just location dictates that I train/race for a road/xc/track based club. Most of my structured sessions are based around 5km/10km/marathon type sessions, and I have to fill in the hill-based stuff on my own, either on the treadmill or trips to the fells.
But I compete in the road Relays, and love the cross-country, and have done the odd track race too...
I do think that a lot of Fell-only runners do tend to neglect a bit of speedwork, to their cost.