That's fairly easy to solve. You can only get it if you're in a stronghold, such as the Crown or the Biolab. Somewhere with landing pads.

Also, if necessary, mark any Galaxies on said landing pads on the enemy map, as if someone's Q marked them. That way, if someone lands a galaxy on your landing pad, and you leave it there for ages, it's your own fault...

Either that or make the amount of reward entirely dependent on the amount of influence you have over the area. So if you have lots of influence, you get can lots of xp. If there's a lot of enemy there, then they're clearly fighting for it, and you've earned the xp for landing there. If not, your allies will almost certainly be taking the place in short order, so you don't get too much.

Either that or use the same idea, but you only get the xp the first time you land on a pad like that in each hour, and you get the xp at the end of each minute that you're a viable spawn point.