You can make a Christmas cracker
put the treats in a toilet roll, wrap nice paper round the the toilet roll,extending over the ends,then twist the ends (holds it all together without using sellotape or string). Your hammy will love trying to get inside. I doubt they would eat the wrapping paper - never had any problems with that - and if they did take some for nesting it wouldn't do any harm really - but they tend to be more focused on getting at the treats!
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