There are many places where this is fairly normal. Leeds is a prime example, most bits of card with a hint of Orange will get you OUT of the gateline. Perhaps a little less on the way in.
Sheffield is a Station I use(d) frequently, it’s my nearest (I suppose it is equal to Nottingham in terms of time) larger interchange station. I think I can count on one hand the number of times I have SEEN ticket checks on the platforms there, and have never had one myself. Meadowhall on the other hand, at least 50% of the time I’ve arrived / departed there.
I've always looked at Leeds as the opposite as the barriers are never open (to the extent that they'd rather close off the South entrance altogether than have them open and unattended some of the time) so you always have to present a ticket of some sort. Obviously you can never tell how closely they will be inspected !