Some small pubs might have limited opening hours, I have come across these on my travels.
The alarm bells for me are the wanting to mess your boundaries around, offering extra money and involvement of alcohol.
I always decline extra unless it's a discreetly offered tip once I'm there, anything I do is in my rate extra does not change my terms and conditions or screening which includes checking the property exists, taking steps to increase chances he'll be there, and in a state in which I can deal with.
Telling you to get a taxi is another alarm bell, you need to be in charge of your transport whether you drive, taxi, bus it's for you to arrange. His suggestion sounds like he intends you to be over the drink drive limit.
His repeated texting when rejected is not a good sign either, so distressing when this happens. I'd just tell him to cease contact, if he continues you'll approach the police on grounds of unwanted contact and harassment.
Most licensees do not want any trouble with the police, as I understand it puts their suitability and license at risk.