That's different. In Jeremy's situation people will do allot for hi
If they believe he is innocent, because to them an innocent man is in prison.
It's more about having a purpose in life. Feeling important by engaging with a famous person and getting on TV and the radio.
They may feel powerful that Bamber is reliant on them and appreciates their help.
They may feel there is a slim chance of him being innocent. Especially if they blank out the things that highlight guilt and just use Bamber as the source of information. None post on forums I believe.
They will certainly feel that there is a chance of him getting off on a technicality. Which would mean they can then justify their support to everyone.