West Ham are underrated. They have the second largest capacity stadium behind Man Utd and were told, especially by Spurs fans, they would never fill it; but they have been exceeding Spurs and Arsenal. Although I think they use the Arsenal model of tickets sold not entrants as it's very unlikely everybody is able to turn up due to unforeseen circumstance; ie accident, family trouble, illness.
To add a train perspective the Saturday 1804 Paddington to Penzance was like a football special when you had 3pm kick offs there would be West Ham, Arsenal, QPR, Millwall and other supporters going home, some even into Cornwall. Plenty of drinking but I never saw any trouble.