All of this. ^ I think a lot of the negativity and hatred and anger towards people in social housing is borne out of bitterness and jealousy.
Some people who are buying/have a mortgage, are forking out maybe £1200 to £1800 a month for their mortgage, (or more,) and are having to pay for any repairs and maintenance, that can often run into thousands. Tens of thousands in some cases. Complete new heating systems, new electrics, a new roof, new windows, new doors, fixing damp issues, etc etc.
And they see someone who has a social housing property paying less than half of what they are paying for their mortgage, (sometimes a third of it!) and getting every last repair done, and every last bit of maintenance, new kitchen, new bathroom, new windows and doors, new heating system, new electrics etc.... (all included in the rent of course.) And some people have the rent paid if they are not working, (ie; parents of young children, older people, etc.....) People who are homeowners don't get the mortgage payment paid if they end up out of work. (I mean, obviously they shouldn't, as why should the taxpayer be paying someone's mortgage?) 
So they see people having what they perceive to be an easy cushy life with a lifetime tenancy that has a modestly priced rent compared to what they're paying. Along with a lifetime of security, and all the repairs done, free gas servicing, free electric checks, remedial work, planned preventative maintenance, and so on.... and it brings out anger and bitterness in people.
But don't hate the player, hate the game. ANYone who has a chance to have a lifetime tenancy for £400 to £600 a month rent, and everything covered (all repairs and maintenance and remedial work and planned preventative maintenance - like paintwork on the outside of the property and roof maintenance etc,) and the rent paid if they are not working/lose their job, would be a fool to not take it.. And they would be a fool to let it go when they have it.
As has been said, there needs to be a LOT more social housing, so that anyone who has a household income of say, £40,000 a year or less, can qualify. (And actually get a social housing property if they wish.) The idea that anyone who has say, three or four hundred pounds a month more income now (than they did when they got their social housing home say, 7 to 12 years ago,) should give it up now, to someone more 'deserving' is farcical. Incredibly blinkered and narrow minded thinking.
If said person in social housing was to give up their lifetime tenancy on their home that has a modest rent, they would have either move into private let, that would very likely be double the rent, or more. OR they would have to buy a property/get a mortgage, so bang goes that extra £300-£400 a month, and much more.... That would put them back in a precarious financial situation, and if they lose their job, they could lose their home, and end up on the social housing list again, and wait YEARS for a social housing property.
So the idea that people in social housing should 'hand it back' if their income goes up a bit (a few hundred pounds a month) is fucking ridiculous. No-one in social housing is driving a lamborghini, going for trips to Dubai every few months, wearing diamond encrusted shoes, and wearing Gucci, Ralph Lauren, and Chanel. Most people in social housing live modest lives. The vast majority of people who have qualified for social housing in the first place are not high earners. They never have been, and they never will be.
Social housing often isn't even super cheap rent, it's 'affordable' and reasonable.
Private let rents being so ludicrously high, and house prices now being high (making mortgage payments high for many) make the social housing rents seem very low. But they're not. They are modest and affordable. Not very low.
As I said, don't hate the player, hate the game. The social housing tenant haters are aiming their vitriol and ire at the wrong people. Why be so angry and resentful that someone is comfortable and happy and has a secure home for life? It's not a good look to resent someone's happiness, comfort, and security.
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