Why do supervisors hide my rights from me? the question title above is deliberately provocative. 
I am in the UK. A few days ago I have explained my situation - many problems with a Department that was not able to support me adequately.

Generally, both my supervisor, co-supervisor (the co-supervisor has just become a lecturer, so he is probably just inexperienced) and head of department (who was the arbitrator during my viva, after I raised all my problems) have constantly avoided to discuss with me the reports from my examiners, just recommending (almost demanding) that I do follow those. They have constantly denied that I can appeal to a "revise and resubmit". However I have recently contacted the student service of the University, and there I was told that not only I can appeal for further opportunity to submit, but that I can also submit a complaint to dispute tuition fees liability.

Now, I can understand the latter option was avoided - nobody is happy with money, but why was the former option (appeal) completely denied rather than discussed? Do academics get some reputation issues if students submit an appeal against a "revise and resubmit"?
I don't know your institution, but it's fairly likely that the right of appeal is limited to a subset of things like:


administrative irregularities and errors (e.g. you should have passed, but the examiners ticked the wrong box).
Immediate mitigating circumstances (e.g. your parent died the night before so you couldn't present a coherent defence of your thesis)
Inherent bias (e.g. you turned up in your favourite Everton shirt and know the the examiner failed you because he's a Liverpool fan)


The precise topics should be documented (properly, on paper) in regulations available from your registry (or however your individual institution labels that service).

In particular, it almost never covers academic decisions, or problems arising from previous poor supervision advice, which is typically meant to be dealt with far earlier in the process when it first arose.