Lol. Yeah. Just a joke. Lol. I didnt even know you could buy a dish this big! What could you get with a 15 that a 10 couldnt get thats the question?! Lol.
You can get dishes much bigger than that if you have the bucks. I worked with 6 meter dishes when I worked for Harris Corporation. Anyway, the 15 foot dish is more focused which makes it more difficult to align it (especially on Ku band frequencies). A 10 footer would be adequate, for now, but it may be necessary to go to a 15 footer when new modulation schemes come out. I suppose it's possible that they could go to 1 degree spacing of the satellites which would require a larger dish.