Why is it when I have been to Greggs, for their chocolate donuts, they have used synthetic cream, whereas for their chocolate eclairs, they have used fresh cream?

Eclairs = cream, donuts = any old tat, its a tradition thing plus fresh cream in a hot donut would lead to something more akin to a soggy pancake.

Forgive my ignorance, but what is synthetic cream?

vile.

edit: http://www.nigella.com/recipes/view/...tic-cream-2850

Revolting! Is that stuff really used?
I use Dr Oetker Whip It in real cream. Klop-fix it is called in the Netherlands.
A friend of mine uses a pastry baker's trick by adding maize (corn) starch that has been cooked with double cream. Never tried that one. Whip It is essentially the same thing, but more convenient.

it`s truly foul.

i prefer creme patissiere, any synthetic cream makes me gag.

Greggs is a business. Synthetic cream comes without all the commercial 'problems' of real cream, and can stay on a warm shelf for hours without going off.

That's why swiss rolls and other cakes with a white sugary 'cream' that have a best before date of 2014 or beyond don't use real cream either. That's why I always buy a fresh cream roulade rather than a swiss roll from my supermarket. It's essentially a chilled swiss roll made with real whipped cream and tastes so much nicer as a result.

In the early days of Walnut Whips, they used real cream. But it became too much of a problem for customers biting into live maggots due to flies laying eggs on the production line, so they moved to sugary substitutes.