If a person supports a group of people based on their own perception of that group. When in truth by supporting them they bring hardship on themselves whether it is physically, emotionally, or economically. Could even be supporting a political party that doesn't in truth cater to them.
Supporting something based on a false perception, and not in earnest would be dissembling.
Dissemble (?), v. t. 1. To hide under a false semblance or seeming; to feign (something) not to be what it really is; to put an untrue appearance upon; to disguise; to mask. [1913 Webster]
If you are justly compensated for the trouble, it's called:
if you are not compensated:
or if the members believes that their personal hardship is justified for the greater good then they are in:
Those are words with more or less neutral connotations.
If you're looking for a word with negative connotation, a group that tricks its flowers into following philosophies that are not beneficial to themselves is in a: