The previous ticket office (the wardens stone hut - at the top of the Xyloskala) is still there. The warden probably still checks tickets of walkers entering and leaving the gorge - this is the only practical way to 'police' who is in the gorge. A couple of years ago the bus company changed the route of the evening bus from Sougia to Hania - it now returns via Xyloscala. As a result a lot of gorge walkers drive to Xyloscala and park their hire cars in the vicinity of the new ticket office. In the evening they catch the ferry from Agia Roumeli to Sougia, then the bus from Sougia to Xyloscala - pick up their hire cars and return to their resort.
Perhaps the gorge authority moved the ticket office to encourage people to visit the museum and shop?