Some fascinating posts on this thread, hence I would like to add a bit more.
Little Chef...did a project on then for part of a module on my Degree. The reason(s) they vanished are complex, but, in part, they became complacent and felt the brand, and the iconic chef symbol sold itself. This changed when Granada took over, plus, apparently, they were a nightmare for suppliers.
Wetherspoons..not a frequenter, as such, but, much depends on the outlet. The one on Oban, being brand new, was excellent as was the one in Stirling...the one in Stone ?...nothing a couple of JCB's couldn't improve ....after a wrecking ball had been employed first.
Greasy spoons...the Lazy Leek outside Welshpool...a loaf of bread cut in two with half a pig inside...well not quite, but as bacon sarnies go, very generous portion and quality bacon.
Breakfast...TH Roberts, Dolgellau ..now this place is quirky to say the least, but, the food, service, quality are all excellent.
Cafe Royal Aberdeen. Again, quirky but fantastic venue...and their breakfast would fill you for a week.
Pride of place, even featured in the ST no less !, has to be "Greasy Lil's" as it was affectionately known, or "The Hollies " truck stop on the A5 just off Jnc 12 heading for Cannock...the breakfast is legendary and genuinely 24 hrs a day, plus, it still does a core essential....fried bread !
Sadly, as with Grey squirrels taking over from our native Red, so the hash brown has been allowed to desecrate UK breakfasts in lieu of fried bread.
Actually, the best all day breakfast were the ones made by my late partner...who was adamant, and I wasn't inclined to argue, that, pure lard was essential for cooking all the ingredients in....I should add we only had this indulgence 4 times a year.
Avoid chains at all costs !!! although ironically, Norton Canes Services. first thing Sunday morning I admit, actually did a reasonably priced and portioned breakfast.