I think the biggest issue with all gathering places is to be able to adapt to social distancing measures.
In Italy, the guidelines for shops and restaurants are that 1 meter be allowed between individuals. Obviously with a little adaptation this could be managed in a Walmart, by limiting the capacity of the store and strongly managing customer flow. Perhaps it will become feasible that sports, theatrical performances, and meetings could continue if the seating were significantly reduced / staggered to leave empty seats between individuals. Reduce touch-points by encouraging contactless card or phone transactions, having staff and resources available to wipe down surfaces frequently.
Your average theme park environment could be significantly trickier. Maybe if you cut overall park capacity significantly, half-load shows, re-route lines to avoid switchbacks and encourage distancing in lines... Challenging perhaps, but perhaps better than the alternative of a long duration complete shutdown.
I agree that this half-attempt at limiting gatherings needs to be better defined and applied uniformly. Of course, that means a park closure could come sooner rather than later if these sort of connections are made and 'uniform' bans are quickly adopted.