I don't think it is unreasonable to ask about annual leave, it can be a great bartering tool to get the better employee's out there. Besides it is by no means true that all UK work places give just the national minimum.
Would you rather work for - Practice A. who pays £8.00 p/h, has sick pay and gives 30 days annual leave or Practice B. who pays £8.00 per hour, gives sick pay and gives the national minimum of 28 days annual leave?
But i totally agree on the sick days thing, how on earth can you expect to get a job by making it clear in an interview that you are assuming you'll need sick leave? lol
Besides some of us aren't lucky enough to be able to have sicckness even when we are sick - I have had to book 3 days annual leave for a minor operation I am having and even then I had to change the offered dates 4 times because we can only have 1 member of staff off at a time...