All crystal malts are caramel (type) malts, made from sprouted barley, but not all caramel malts are crystal malts. Crystal, generally produced in rotating drum roaster, is of even consistancy with all starch converted to sugars. Caramal malt can be produced in a heated grain bed, at lower temperatures, where the moister grain, near centre becomes crystal, while the outer drier malt gets part roasted.
Confusingly, Belgian (Dingemans) & American (Briess, Weyermann), call their crystal malts 'caramel malt'.
As Cire pointed out, British beers were around long before crystal malt existed. But so was (true) caramel malt.
For British golden ale, including sugar can help reach the lowish FG for that style, but you'd maybe also do saccharification mash at slightly lower temperature, to produce mostly fermentable sugars (especially, if not adding any sugar).
While for British strong ale, addidion of sugar (or LME) can help reach a high SG target (up to 1.088). But you'd then want a warmer mash, producing more unferrmentable sugars, to get the styles higher FG (or add dextrin malt).
Quickly looking through Wheelers British Real Ale book (3rd ed). Of the 16 bitters listed, eight include table sugar, at between 5% and 15%; seven include crystal malt; while four include neither.