This situation is a result of the club's at times average and at others appalling away support. Over the last few seasons I have witnessed the club's away followings and their totally unpredictable nature.
Promotion season: Watford away (night)- around a thousand.
Last season: Middlesbrough away (Sat)- Nedding a win too secure survival, not many more than a thousand.
This season: City away (Sun), First local game of the season, 1,500.
This will have clouded the club's judgement somewhat, yes they should have worked out that for big games the fans ALWAYS return, Arsenal in the FA Cup, over 4,000 sold in three days. So the club should have realised that Celtic was one such game.
Yes, the club is probably at fault, but the big drop in away support over the last three years is also a factor.