I don't think its about a strength of belief. I think their material conditions were comfortable, and they realized that in order to actually do a revolution it would require dismantling the systems that currently provide them with comfort, and so they didn't want to do that.
You can categorize this under, "Sure socialism would be nice, but I'm not willing to do anything to actually make it a reality."
This is simply a result of people not wanting to rock the boat, and taking the path of least resistance. Were their material conditions more dire I am sure they would have been a lot less reluctant to take action.
