THe money to be made is insane as well. Muddy Knees claimed to have 500,000 listeners per episode last year, and the average rate for podcast advertisers is roughly $18 per 1000 listeners for a 30 second ad and can be up to $40.
Each episode has at least 4 ads, so you're talking £40k an episode.
According to YouGov, it's the second most popular radio programme for men in the country -
https://yougov.co.uk/topics/media/explore/radio_programme/The_Totally_Football_Show
And it's main demographic is Men 21-40 which is a gold mine for advertisers.