I remember 'Love Thy Neighbour' and loathed it, not because it was 'racist' but because it wasn't funny. The 'novelty' of a racist black man wore off after about three minutes, but they went on flogging it week after week.
'Till Death us Do Part' was far better, with far better drawn characters, excellent writing, and the matchless comedy timing of Dandy Nicholls.
Times and humour do change - as does what is acceptable. I am with Dave, I have a very dark sense of humour, and do appreciate humour where none is immediately apparent.
Jimmy Carr sums it up - he likes a laugh followed by a gasp, as though his audience have found him funny, but are appalled at themselves because of it.