Ha, likewise - I used to tour really far (300-600km in a day sort of things) and sometimes I'd make the whole trip without a hitch, other times I'd get several flats in a day. It became second nature to assume my bike was going to get a flat soon, so I still carry it in a saddle bag everywhere I go.

Of course she thought it was silly too, but yeah, we cycle everywhere and I've fixed a lot of flats now.

In their defense, I only figured out why you should bring kit everywhere because I've been stranded badly, totally unprepared. I was finishing a 400km ride, around 40km to go at 1am, and my tire went. It was cold, raining, low/no traffic, no cell service for most of the trek back, etc. I got home as the sun was rising, haha.

600km per day by bike? that's an average of 25km/h for every single hour of a day ...

You're right, what I should say is per continuous riding session - I used to take more like 38 hours for 600s (just under the cutoff, haha). There are breaks, usually 30m max, but I tended to average more like 18kph over complete ride. I wanted to reach 20kph, but had a kid instead – that kind of threw a stick in taking long rides.

Here's more info if you're curious, it's a fun sport called randonneuring: https://en.wikipedia.org/wiki/Randonneuring

Here's an example 400km route from an area near me run by the BC Randonneurs: https://ridewithgps.com/routes/33536016

It's a great way to get to know areas better. Very meditative, challenging, and rewarding.