Well you had both better let the holding company, owned in part by the boroughs of Greater Manchester this. Because part of their large expansion plan at the airport is to have it linked to large parts of it's customer base with direct trains running from the various hubs such as Manchester, Liverpool, Leeds, York, Sheffield etc. And the reason for not just making Manchester Airport an exclusive North West product is that they are expanding their long haul routes, and passenger numbers from all over the North of England are growing at a pace. This is causing serious problems, particularly on the M62 which almost daily sees long queues, accidents & delays. The train, is seen as a alternative to a growing number of people, but in order to attract them there needs to be a way of getting them from their home station, through a hub and onto the Skywalk at Manchester to head for their terminals without numerous changes of trains and even modes. If this is supressed by curtailing long distance services, there will be more traffic on the roads around GM.
There are plenty of airports that require multiple changes of mode to get onto towards passengers main destinations. Many of these are legacy systems with newer, bolted on solutions to try as resolve growing transit issues. It doesn't mean that they are the right solutions for other airports, or even the ones they serve. Watch this space at Heathrow when the realisation that the third runway and additional terminal drives the debate about linking the airport up with the network without having to change in London over the coming years!
I wish people when debating this issue would stop dreaming of some lovely Manc-Bahn system for Manchester, with a Heathrow Express type shuttle to service long distance passengers because neither is going to happen. I've repeated this goodness knows how many times, but GM's airport is expanding, rapidly. That means more punters either coming in on trains, or if the provision isn't attractive further clogging up the roads. That the good folk of the Style line don't have a high frequency, clockface metro service is unfortunate. But let's be utterly frank here, Greater Manchester has a far better public transport system than many other large metropolitan areas, cities and towns. And it benefits greatly economically with the large amount of employment (around 22-24K people I believe) that the airport creates directly let alone the secondary employment & economic benefits it brings.
So getting a handful of long distance services through Manchester shouldn't be an issue, it requires some simple tweaks to things like stopping patterns & timings, and in the longer term would benefit greatly from the rest of the proposed development currently gathering dust somewhere in Grayling's office. Stop the direct airport services and you simply move the problem to another part of the infrastructure, making things worse not better. It is what it is I'm afraid, Greater Manchester is heavily invested in it's airport & it needs more passengers to justify the vast amount of investment going into it's expansion. I have mentioned previously that people need to look at the bigger picture, the rail network is not some parochial train set for Manchunians, it is part of a wider infrastructure that helps drive the economy in GM and beyond.