I do both ways. Sometimes I remove them and sometimes I ease over them. When I was working on Judy Niemeyer's Bali Wedding Star, some of those seam joins absolutely could not be done accurately without leaving the pin in. I actually had to press the seams open and then pin through the middle and before the join. My ripper and I got to be best friends on that project.
I have been sewing for over 50 years and for many years it was only clothing. We were not taught to take the pins out, but to put them in parallel and sew over them. I believe that was because in sewing clothing there are a lot of times when you are easing extra fabric in...think set in sleeves and bodices with the curved lines up through the breast area, rather than darts. If you remove the pins, you will never get those seams sewn properly.
Quilting is so much easier than clothes for me. Most times I only need the pins when I am doing curved sections. But when I do, I will sew over them in a heartbeat...going much slower than my normal medium speed. Years ago, I hit one with my big Brother going extra fast, and it did break my sewing needle and the pin. The pin hit me in the cheek. That really got my attention. Now I sew slow and steady if I have to leave the pins in.
As with everything else quilting, it almost comes down to a personal choice.