Is it ilegal for a company nnot to pay you holiday entitlement?

at my place,if you are absent the day before your holiday starts or your anual leave,even if your dying with flue,you do not get your holiday pay,why can companys do that and where or who does your wage go to ,its happened to loads of people there,surely you can appeal,or do the fat cats sitting on there es get ritcher ,please anyone