Do I really need travel insurance in EU Countries?

The simple answer is yes. Without travel insurance for EU countries, you could face medical bills even though you hold a European Health Insurance Card (EHIC). Although UK residents with an EHIC can access healthcare in mainland Europe, this is to the same level as local resident of that country – not the same level as is provided by the NHS here. This means that there will usually be a fee to pay – and it certainly does not cover repatriation to the UK if needed.
To give you an idea of what these costs could involve, in September 2011 it was reported that the average cost for falling seriously ill abroad was in excess of £2,000 – but that depends on the country you are in and the nature of your illness. Whilst a heart attack in Greece could incur a medical bill in the region of £12,000, a simple visit to outpatients for a nasty looking insect bite in Spain could set you back £200; and for all you revellers heading to Ibiza – treating a head wound from a fall might see you nearly £500 out of pocket.
When you have the right travel insurance for visiting EU countries, these excess medical fees are waived, so you don’t need to worry about paying for treatment.