During normal non-festival summer there's also the grass either side of MMW for people to sit upon and bimble along, whereas these are now limited by all the important poster substrate barriers.
Considering the considerable cost of installing a huge circus tent and some interlocking plastic duck board stuff it wouldn't be much extra for a couple of signs (and flashing lights) warning the people leaving the circus-tent area that they're about to walk across a two-way bike path (from the bike side of which bikes are not technically permitted to stray), just in case they were thinking about stopping for a chat on it.