Engineering,why is it so?

Engineering seems to be a tough and very demanding discipline but the salary doesn't seem all that attractive(this is in UK) A typical university graduate will start with about �18000 and rise to about a maximum of 28000 after so many years of working(correct me if i am wrong but that is what i always see on advertisements).Compared to equally demanding fields/proffessions it seems like been underpaid.Could u please give me your opinions(i'd like to study it but this puts me off abit).Thanking everyone in advance .