Have these ever had catering in recent years?
Which still has onboard catering and has recently upgraded the offer.
So offers no real space advantage, as a trolley is mobile so can be moved if in the way.
But you'll still need staff to stock and maintain the machines.
1. Not in this decade sadly. But would be good for such a distance (1hr - 2hr journeys)
2. For TPE, given that train can be quite full during weekends, trolleys may not be best, especially need to push through passengers.
3. You still need space to store the trolley, which the machines may still occupy similar stationary space
4. For re-stocking, you just need staff to do that at stations, by station staff, not requiring them to travel on the train the whole day.
Not sure I'd say there is any 'food' selection, just snacks.
However, a third refrigerated vending machine could be added that can offer sandwiches and even easy to microwave products (obvs needs a microwave installed) .
Could be self service but with a member of staff overseeing it as part of other on train duties. Needs to be sensibly priced , no extortion captive pricing.
Long distance services could still retain a better offering with a kitchen if necessary and staffed.
Refrigerated food would be quite risky as you don't know how the demand fluctuates and may exceed the rather short shelf life (e.g. 3-5 days).
Though I would also welcome this, as really want some hot food on some mid-distance trains, especially on LNR services.
I guess this would probably be better in Speculative? I'll ask for it to be moved.
As for the actual idea - I guess it could happen, but honestly vending machines at stations are so poor anyway most of the time that I'm not sure replacing the on-train catering with the same thing would be an improvement in any way... I guess they could install better machines with a better range of products on the trains however
Still, an improvement, as you get much better coffee than the instant coffee that you can get from a trolley.
Also, staff may not always be available to sell snacks & drinks, while a machine is available always.
(Machines on Japanese trains, especially on those Limited Express / Shinkansen, with more variety of snacks and chilled & heated bottled drinks available)