On the LM Euston Division in the 1980s the split was...
Football charter trains were organised by the football clubs themselves (or the accredited supporters club) and tickets would only be sold to season ticket holders/registered supporters. The organisers would steward the train.
Footexes were relief trains on which all other supporters travelled, at the normal fares, to keep them away from the general public. These would usually have a contingent of BTP officers in an attempt to keep order.
Football Charter: In the late 1960's Birmingham City FC inaugurated the "Beau Brummie Travellers Club" for which you registered, got a membership card and a pin badge. They ran a members-only football charter from New Street to Rotherham on 18th February 1967 (I've just looked it up) for an FA Cup 4th Round tie which I signed up for; it was a single Class 25 from memory. The coaching stock must have been fitted with some sort of rudimentary broadcast system, because the game finished 0-0 and I recall the Blues' captain, Malcolm Beard, having to apologise to the train on the return leg for missing a penalty!
Footexes: Three other Birmingham City away games I attended in the same era were not so pleasant. Leeds United was the worst, the Birmingham fans were corralled by the local police outside Leeds station and
escorted frog-marched to Elland Road, surrounded by police horses. Leeds fans ambushed the return train not far out of the station, throwing missiles from an overbridge; a corridor window in the compartment coach I was in was shattered.
The game at Ipswich passed off without any problems, but there was trouble at Norwich station on the return journey from the fixture there - I recall Birmingham fans throwing missiles (bottles?) out of the windows at the train in the adjacent platform as we departed. It was also memorable for an incident on the outward journey. I remember what the haulage was quite distinctly, because when we were bowling at speed somewhere across the Fenlands, I decided to find the loo or the buffet or something, went to the end of the corridor, pulled open the gangway door, and found myself staring at the back cab of a Class 47

........ Guard duly alerted!