From my perch at Zabaldika, I can agree with you. Early in the morning I have a spot where I sit, and can see many of the pilgrims coming from Zubiri skirting the field that leads to the area de descanso. I am not really sure why so few take the trouble to climb the short but sharp hill to the church. Perhaps they don't have it in their guide? The next climb is longer, and meets up with the path from Zabaldika church and albergue. Then some need shade, so opt for the tree-lined river path leading to Huarte instead of to Trinidad de Arre. Most pilgrims looking for a bed come from Roncesvalles, so they don't really get here till after the albergue opens at 2.30. Having said that, some appear before ten a.m, see the place and decide: this is for me, and stop here. There is nothing here except a beautiful location! A welcome of course...
The numbers vary, last night there were only two. Numbers range from two or three to the max, 18. What I hear from pilgrims echoes what you say, Mike. No need to panic.