Aggravated offences

I was on the official website of the Scottish Parliament today to get the latest on the Sexual Offences (Scotland) Bill and came across a Bill that I had not heard of prior to today.

The Offences (Aggravation By Prejudice) (Scotland) Bill was introduced to the Scottish Parliament on 19 May 2008 by Patrick Harvie MSP. The aim of the bill is to make provision about the aggravation of offences by prejudice relating to disability or to sexual orientation or transgender identity.

This subject, while unaware of a bill on it, has entered my mind many times before. Personally, I am against aggravated offences. Why do we need aggravated offences, what purpose to the serve? Some are introduced to bring equality to the system, but I fail to see how this makes the system more equal. Surly a serious assault is a serious assault and regardless of its motivation should be taken just as seriously as any others serious assault? Why should a serious assault be taken more seriously if it is deemed to be racially motivated or motivated by a persons sexual orientation than if it was just some random attack or the motivation was that X had slept with Y’s wife?

This really confuses me. Opinions are very welcome.