Certainly a valid question and also a concern. We all know that keeping a spare in the wallet is not good for the long haul.
May I humbly suggest that placing one or even two in the wallet prior to an anticipated evening of fun out on the town would be the recommended practice. We all carry our keys in a pocket, yet we do not sleep with them in bed.
In summary, take them when a need is anticipated, just do not resort to the wallet as a storage place. The Night Stand, or the drawers in the Bathroom are both excellent places to store them.
Great topic and one that needed to be asked.
By the way, the topic originator appears to be endowed.