Is it fair or legal companies can evade Corporation tax by declaring themselves as charities.?

Many big business in the UK have charitable status so they can get away without paying taxes.The UK is losing billions by companies like the co op not paying taxes.In theory they are not to make profits but in the real world they just have to reinvest their profits or increase pay and bonuses or give dividends to their customers who are the shareholders.This gives them an unfair advantage over companies who pay tax.Can the UK public still afford to to subsidise these business by having to make up their unpaid taxes.This should be taken to the EU court for unfair trade.