Exactly my thoughts. In theory returning 2,000 or 4,000 should not be a problem but if you put them in a handful of blocks then they going to become enveloped in each other's exhaled air especially if the wind circulation is low.On our local news tonight, they showed a couple of stadiums with fans in, Portsmouth, they seemed to be spread across the stadium (sensible), but at Reading all in one stand and the "distancing" looked shite to me. Oxford had people in different stands, but only small areas of those stands, so distancing again compromised.
Clubs trying to keep the extra cost down (less stewarding) ? If so it's not very clever.