I don't know about the rent but 800K a month is high. BUT its only 26,000 a day. Every time we go in we always spend at least 1,000 Baht - 26 customers a day rent paid. BUT that's just the rent. Wages, band, electric, gas, Police???? Rent's just the tip of the iceberg.
The bands that the Irish pubs have on, in my opinion, spoil the pubs. I don't need some Thai trying to sing Nirvana in an Irish pub? A few years ago, Molly's & Scruffies used to have 'Farang' bands and it was good. For me band comes on, I leave.