This has been a great read.
As someone who first went to the Bridge in the 80s (my first home game was the 82 FA Cup QF against Spurs), it used to amaze (and encourage me) that our away support would sometimes be seemingly even greater than our lower home attendances. I was a kid with my uncle in 82 but was at games under my own steam by mid 80s and was always struck by fact we seemingly had a fair weather home support, and a constantly brilliant away support.
Someone made point about how expensive we were in 80s (Ken Bates has loads to answer for, good, bad and ugly) and that's possibly part of it. The first time I ever went to Chelsea on my own, I got there, and I didn't have enough money to get in. It was £3 and that was a LOT then. I'd have technically been a "child" at this point, and £3 was loads. My cousin was a Spurs fan and I asked him how it cost to get into White Hart Lane; I can't remember the figure, but it was a lot less than £3 and he didn't actually believe me that that was cost of getting into The Bridge.