A visit to Chateau du Granspettte really sold me on grass/matrix pitches; the best of both worlds. Much more pleasant than the surburbian gravel look and feel whilst solid underfoot. The new stuff is a lot more subtle than the holed concrete slabs I've seen at carparks, and they're better than tarmac themselves. There is good info on this for home use on the 'preparing grass' thread. It has real benefit on the site scale too. Would negate the need for any fines policy for runing grass. Not to mention the requirment for pulling out stuck units. Naurally it comes at a cost, though commercial scale would presumably be significantly reduced per m2. It would also potentially allow extension of the season. Perhaps the clubs should investigate? At the least it would be good at the vulnerable corners of pitches.