Hiya Tyke,
I think you might have got your wires crossed - Managers are believed by the Breweries to be cheaper ( Not Tenants) though I have no knowledge of the FILO present arrangements.

My understanding in the average English pub is that a Manager gets a wage / salary - so he/she is (relatively) unaffected by sales therefore there is no incentive to work harder or institute ideas to get more punters through the door.
A Tenant purchases a lease, and also pays a rent generally to the brewery who owns the pub. The Tenant is obliged to buy beer etc from the brewery at prices set by the Brewery.

Put VERY simply , you're more likely to get a stoppy-back or a late drink from a Tenant because the Tenant has to fill the Till to pay the rent , so , if the Tenant can get punters through the door by having a folk evening or whatever other type – then why not ?
A Tenant try other revenue raising activites i.e. probviding meals / food / putting on entertainment etc.

A Manager just finds THAT situation more work, so they are not inclined to put themselves to the trouble.

I must stress again I don't have any knowledge of the present set up at FILO , but it is a shame for all like minded Folkies and other visitors to Whitby – especially with a great fish and chip shop across the road .