Alas, the thread seems to be degenerating into homophobia, whether tongue in cheek or otherwise. On reflection, can't actually see the harm in recruiting (as opposed to participating) at gay marches (it brought immediately to mind the fire sercive participation in the big march in London), however the OTT PC culture is such in today's Air Farce that it is easy to set the antennae twitching! I wouldn't put it past the MoD to decide it would be a great idea to include a flight in a gay pride march from a "corporate comms" perspective, which seems to be our sole reason for existence nowadays.
The point about supporting arms fairs is a well-made one and the brown-nosing we get up to, often with the most unsavoury characters does not sit well with our assumed "ethical" values.