Why would anyone want to risk running out of fuel?

Fair question!

I assume they don't want to visit the filling station too often. Maybe £60 every other day feels worse than £120 every four days?

Oh and yes I often fill up that regularly sometimes a full 85l tank twice a week. 2019 D5 HSE Lux SDV6 Indus
55 D3 SE
98 MX5 1.8 RS
gone 17 older variants of FFRR

I've had my old TD6 down to 0 but filled up very shortly after ( i knew the Petrol station was only a mile away.)

Ben told it's not good to let it get too low as there is often a lot of muck in the bottom of the tank which could effect your filters or injectors.

Just to buck the trend mine pretty much always goes to zero and I still drive as out and about round here filling stations can be few and far between. I carry a jerry can for emergencies but have never had to use it. I reckon I have been 20 miles before with zero range showing. Obviously sucking up crud from the fuel tank can be an issue but I think its less of a problem nowadays with detergents in the fuel but probably not to be advised!
My Isuzu though goes from light on to coughing in about 5 miles! Then it cuts out unless you point down hill as happened out on a call and still managed to drive 10 miles to filling station where it cut out on forecourt! Still started first time though once full. Magic these Jap cars!

I have been caught out (granted before I replace my fuel pump) where it was low and the light wasn't even on yet (had the light on before) and it left me by the side of the road. This could have been the tank balancing pump issue but still. The tank was quite low at the time (so not the standard 1/4 tank problem). MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!

The thing is if you dont do it every now and again gunk is more likely to build up in your diesel tank and then when you really need it and go past 1/3 of a tank the balancer pump is going to be found to be duff so better to run them every now and again.

Also for the TD6 i was under the impression the balancer pump always runs but isn't exactly loud so not easy to here when inside the tank and under interior foam and carpet and seats  FFRR MY06 facelift With TDV8 Alloys Zeros/ATR's
Mantec Sump Guard, Rigid Load liner, MY10 BT upgrade.