Sentencing. Shouldn't the Punishment fit the Crime?

[Mill Wheel]

In the light of various cases, but most recently the "Black Lives Matter" protest at London Airport, is it not about time that a degree of even handedness was applied to sentencing?

At the moment it seems to be a lottery, with varying sentences being handed down for similar crimes.

The BLM airport protest is a case in point - with what appears to be ludicrously lenient sentences being handed out!
http://www.dailymail.co.uk/news/article-3788741/Bl...

Daily Mail said:

To be committing aggravated trespass, a person must be both trespassing and intentionally obstructing others from carrying out ‘lawful activities’.
By refusing to cooperate with police, the Black Lives Matter protesters committed the offence.
The maximum sentence for the offence is three months imprisonment or a fine of £2500.
First time offenders usually get fines of £200 and £300.
Despite the disruption caused, the judge in this case gave all nine a conditional discharge, which means they will not be punished unless they commit another offence in a specified period.
The group also had to pay a £95 court fee, which they reportedly paid on their debit cards.

Compared to the anti fracking protest in Surrey last year:
http://www.getsurrey.co.uk/news/surrey-news/anti-f...

GetSurrey said:

A pair of anti-fracking campaigners have been ordered to pay £295 each after they locked themselves together at a drilling site near Horley last year.

When it comes to sentencing, does it not serve justice to give an explanation of sentencing, so that the public can see when some offenders are treated leniently?