temptation, because I don't need any food to take with me on the train, I'll be eating dinner within an hour of getting home!

frustration, because:
- there never seem to be enough staff to cope with the demand (they seem to wait for the queue to become 6 or 7 deep before calling a second member of staff over, who saunters over with all the loucheness of someone who doesn't have a train to catch);
- there always seems to be someone in the queue who is doing an entire week's shopping, dithering around in her purse for the right change whilst six people behind her miss their trains.

so yeah, M&S food outlets at train stations: good thing or ban request?

That's right: colon_closed_bracket: addressing the issues that matter.