I think that's quite an important distinction from 'theft'
There's no loss, certainly in my case, so difficult to see where there's any 'moral' problem. And I adhered to the terms and conditions of sale - so it's not even a case under civil law, without the absurdity of considering the criminal idea of theft!
I think setting out to 'rent' clothing is perhaps different in a 'moral' sense (though personally I don't really care if people do it, tbh). But perhaps there's also a 'moral' issue with buying clothes for a one-off use: wasteful.
There is a loss though, returning goods does cost the retailer money. They have their terms and conditions and statutory obligations but if people take advantage of those/seek to exploit them then I think they'd be right to start banning people.
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slight diversion:
I do wonder how long it will be until some people start to moan more about access to private resources owned by companies etc.. for people who've previously demonstrated **** behaviour/abuse of those resources. I mean with electronic retailers it is quite easy to look at someone's history and ban them from a using a store again. Currently there is an issue with social media and people being banned from using certain platforms - the current pov among many is that this is fine as they're clearly bad people/"nazis" etc.. (though these bans and demonetisation have affected people on the left too).
It is already fine for shops to ban known repeat shoplifters, though this generally relies on individual shop workers and security personnel recognising them.
It is also fine for stores to limit access - for example some boutiques in London will require you to ring a door buzzer before being admitted, they don't want any old riff raff in there.
One thing that I am interested in seeing is how it pans out with the likes of amazon or other tech firms getting into retail - this is something politicians are already looking at in the US.
For example if you need to be a signed up member to use a physical store with various image recognition technology to automatically see what you put in your basket etc.. and automatically bill your account when you exit then shop lifting is basically eliminated in those stores aside from some edge cases - any scumbags simply aren't allowed in in the first place. If similar measures are eventually adopted by all supermarkets then repeat scumbags can't get into any of them, anywhere in the country. They're left to independent corner shops and food banks or whatever business wants to set up to cater to the high risk scumbag market.
That could easily prompt lots of bleating/people demanding that privately owned stores have to admit everyone even if they're known to be scumbags who have robbed from the business on multiple occasions...
I suspect that social media is going to be more heavily regulated at some point in terms of how easily they can ban/demonetise people and as technology progresses the ability of large stores to control who gets to come into their business and trade with them will become more heavily regulated too in terms of who can be banned from their premises and for how long etc..