I'm sure you know this, but grams are a measure of weight but pints are a measure of volume, to compare them in this way you need to know the density of the yohurt. Assuming its density is that of water, one, 500 grams is indeed more than a US pint (473 grams) but far less than a UK pint (568 grams)
Without measuring the density you could check its 'over a pint' by pouring it into a pint glass. Knowing Asda, I suspect there might be some 'salesmanship' being employed here!
However, having presumably cleaned up their act after the recent £700,000 food hygiene fine, they will be keen to get their sales up to scratch again and price cuts are the obvious way to do it.
I didn't compare them, you did, I only stated the sizes.
I am surprised that yogurt is sold by weight, being a fluid, in my eyes it would be normal protocol to sell by volume but I suppose then there would be a risk that the manufacturer would aerate them.
Humans don't relate to weight very well, hence I gave an idea of the volume that was purchased. I stated the gross volume which I suppose could be misleading and perhaps I should have said either "pint sized" or "about a pint".
As I stated, this wasn't an offer, this is the normal price across all stores, it hasn't been reduced to compensate for the localised fine Asda received.