Gransnet is not a site for making one special friend, it is for chatting online to a lot of people. The coffee meetups are the icing on the cake for those who would like to put faces to the posters they have sorresponded with.
If you only want to meet someone you are 100% sure you have a lot in common with it could take you a lot of checking out of profiles. Take a chance!
It is not a dating agency, either for straight or for gay people, so you have nothing to worry about there.
Why not join a few people who are already meeting? If you have posted a few times on the forum and read what they post you will know them a little.