1. I can wake up and glance at the time instead of having to lift something up and put it centimetres from my face to tell the time.
2. I can do sports without the glasses falling off, getting mashed into my face, etc.
3. I look a lot better, with a -13 prescription, my glasses were heavy and thick
4. My nose and ears aren't in pain from carrying the weight of my glasses all the time.
5. I'm not having to constantly adjust my glasses whenever my nose sweats a bit.
6. I'm not completely blind any time I have to take off the glasses, like when I take a shower or go in a pool, or especially swim in the ocean where there are big waves.
7. I'm not utterly helpless because I'm blind if I lose my glasses. If you're blind without your glasses, and your glasses aren't where you expect, you can't really use your eyesight to find them.
8. I don't have to deal with all the problems of using and potentially losing contacts.
9. ...

For me, before I got laser surgery, I was once swimming in the ocean at a very big and popular beach. I was wearing contacts because obviously wearing glasses in the water is next to impossible. I got hit by a big wave, tossed around, and lost my contacts. Now I was almost completely blind, in a foreign country where I knew almost nobody, and trying to find my beach towel and bag among thousands of others. I actually can't remember how I resolved that problem, but I do remember the massive stress and panic being blind like that caused. When I got back from the trip, I got my eyes fixed within a year.