This doesn't make any SENSE!
The original version is, "To each his own."
In other words, "To each [person shall be given] his own [property]."
I have no quarrel with replacing 'his' with 'their' as a neutral-sex alternative, but it should be "To each their own."
Otherwise, it means, "Each [person shall be given] to their own [property]." Which is rubbish!