I don't agree with that, because that is exactly what I do. I have a hot wallet on my phone with usually less than $100 worth of bitcoin on it. I use this to make purchases in person with my local merchants who I know accept bitcoin. I'm buying things like groceries or electronic accessories such as spare cables, so usually well under $100. When it gets low, I top it up from a cold wallet at home.

If I plan to make a larger purchase than that in person, then I'll either load up my hot wallet in advance or take a hardware wallet and take it with me, depending on the value we are talking about.

Fair enough, but that goes back my original point. If you are entering in to a marriage and already planning to hide all your bitcoin from your spouse, then you should have signed a prenup.