They're entitled to ascertain whether the client is fit to travel or not and whether the destination id within 30 kilos. Although I'm not aware of any provision within the regulations, NTA have also told us that we can refuse a fare on safety grounds which presumably entitles drivers to fear certain areas or travellers or immigrants or whatever. I actually had a woman in the car a few months back complaining that the taxi was going to cost her the guts of a tenner because Dublin Bus had terminated her bus service (to Ballyfermot) due to anti-social behaviour. FFS, says I... I should be charging you danger money if the buses won't go there... aah but it's happening all the time, says she...