Since you ask, you simply make a conscious decision. The choice is between the risk of having your possessions stolen balanced against the inconvenience of removing and carrying your stuff (and maybe even the whole bike) with you. There is no perfect choice.
I can think of dozens of factors that would impact the decision that I would make. You can never totally eliminate the risk of having anything left in a public space stolen. Given time and technology, people have broken into bank vaults. All that you can do is to take whatever precautions you deem will balance the risk of theft against the inconvenience of carrying everything with you. Whatever the outcome of the decision that you make, rest in the knowledge that was your choice so you brought it onto yourself.
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My greatest fear is all of my kids standing around my coffin and talking about "how sensible" dad was.