In my opinion, they are a couple of guys trying to look like a larger company, and hence have more credibility by incorporating the word 'VAT' in their quote.
If they were VAT registered, they would charge a higher, more realistic price and show the VAT separately, for ease of accounts and I think it is also a legal requirement to show the VAT separately on a quote.
Probably a couple of chancers!
PS I shop in Aldi (I love their 'Essentials' frozen chicken breasts and frozen white fish!) Nearly half the price of the fresh stuff.
Anyway, on their receipt they show the price of your shopping. If you look down the receipt, you will see the VAT is shown separately, for both 0 percent VAT and 20 percent VAT.