The car I rented last weekend (Oct 30, 2009) from Europcar at Cork Airport Ireland, had 2 bald front tyres and the rear tyres were'nt great either.
They deny this saying that they were 'low but road legal'...whatever that means. They did however agree to change the tyres but only 'approved their swapping out so as you would feel more confident with the tyres. Had the tyres not been changed they would still have been perfectly acceptable to drive'.
A second Kia Piccanto in the driving lot also had a front bald tyre, but Europcar 'failed to see the relevance'
Please inspect all your tyres from any Europcar rental car from Cork Airport, as Europcar refuse to. You can bet your bottom dollar that any accident damage incurred to their cars whilst driving on their 'low but legal tyres' will most certainly be charged to you!