Some galleries/museums have made attempts to deal with the large amount of works that are 'in storage' & not on display. The National Gallery in London, for example, has lesser works displayed in the basement galleries (or did the last time I looked), & Tate Britain re-hangs every year, so the display changes regularly. Glasgow Museums has a public access store. I'm sure there are many other examples across the UK.
As for 'hi-jacking' space, any museum worth its salt will have a mixture of permanent displays, changing & temporary exhibitions from its own reserves, exhibitions of new work & loan exhibitions (the latter two dependent on funding). It's the only way to remain interesting & to offer visitors something new (not for the sake of novelty, but to ensure that they make more than one visit, especially to small museums).
As for 'hi-jacking' space, any museum worth its salt will have a mixture of permanent displays, changing & temporary exhibitions from its own reserves, exhibitions of new work & loan exhibitions (the latter two dependent on funding). It's the only way to remain interesting & to offer visitors something new (not for the sake of novelty, but to ensure that they make more than one visit, especially to small museums).
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