Flight Price and Travel Taxes

I just went to book Aerlingus Cork to Manchester , the price was
€14.99 tax 29.73 = 44.72
Rtn €6.99 tax 35.62 = 42.61 why higher tax?
Total package no luggage €87.33 booking fee €12 = € 99.33

This is pure subterfuge, I thought that they had been told to stop this practice, it would have been more with luggage plus I had to un-tick the insurance.
It makes their special offer emails look silly

Although I dislike Ryanair my Daughter just flew Liverpool to Cork rtn €25 total for 2 people

Tax is charged at a different rate in the destination airport, in this case Manchester.

Sometimes these charges are absorbed by the carrier, sometimes not. This isn't exactly something new, Aer Lingus are copying Ryanair in this as well as all other areas of their operation.

The travel tax in the UK is £11, which adds a lot to the taxes & charges for any flight leaving the UK.

The taxes and charges is made up of several elements and is very variable, the charge can be twice as expensive to fly out of Heathrow compared to Gatwick for example. Each airport sets their own passenger charges and they can vary considerably, sometimes even they will have a sliding scale so the cost changes over the day. Also some airlines negotiate discounts, some don't pass them on - no firm evidence of that just a suspicion based on comparing the passenger charge element between airlines and not always seeing a discount I thought had been negotiated. Then you have to add in the various bits of tax that get lobbed on too. Chances are your daughter got the no taxes and charges deal that RyanAir generally offer if you book far enough in advance, AL rarely offer that deal. Manchester is generally more expensive than Liverpool for flights and charges since it is a considerably larger airport.