@closetnoc appears to be right that these are not rich snippets but what are called featured snippets.
These snippets appear to be transitory as the "eve mattress" featured snippets have been replaced by site links. But looking at two worked examples on www.evemattress.co.uk & shop.silentnight.co.uk it looks like Google favours well structured html elements that are named using words like price (for price) rather than a specific container like a table.
So to answer the question, use well structured html & identify ecommerce elements with unambiguous class/id names.
Google Search "eve mattress"

Page & HTML

Google Search "safe nights silentnight"

Page & HTML
