Firstly, the ''5 a day''guideline is a minimum based on what the government thought it could plausibly convince people here to eat by way of fruit and veg; some other countries are the same, but some have higher daily recommendations. For example, in NZ the campaign is ''five plus'', the WHO minimum is 400g, the USDA recommend between 4 and 13 servings a day depending on the individual, averaging it at 2cups of fruit and 2.5 of vegetable (an average serve is a handful, so 1\3 to 1/2 cup).
Regarding WW, the key is just to be sensible. Listen to your body's satiety levels and stop when you're satisfied, even with 0-pointed food. Use fruit as a supplement to, not a substitute for, your meals.
Obviously everyone has to find what works for them, but do make sure you eat some because we need it for nutrition purposes! WW has already accounted for it in their calculations, with the daily allowance you're given and the way other food values are calculated and rounded.