When my twins were about your twins' age, we made sure they were only using their pacifiers for sleep (nap time and nighttime). I was able to talk my daughter into getting rid of hers, and honestly it went a lot better than I expected. I just explained to her that she was a big girl and did not need it anymore and that the pacifier fairy was going to take it to give to a baby that needed it. At first she was not too thrilled about it, but then she decided it was okay for it to disappear. I think she asked me for it the next day, but I told her it was gone. I remember having some nights in the beginning where she wanted it, but it all worked out. My son was not as willing, and it was harder to reason with him about it, so when we went to the doctor (I think it was at their 3-year-old checkup), the doctor asked if he would give his pacifier to him so he could give it to a baby and that the baby would give him a present. He asked my son what he wanted, and he asked for a car, so they made a deal. I may have had the pacifier with me for him to give then and there, but I honestly can't recall. Anyhow, I of course went out and bought a car and gave it to my son the next day. His sister got one too, of course. I think he cried for it a few times, but in the long run, it was all a lot less painful than I thought it would be.
I think I tried cutting the tips a little also, but like your kids, they did not care and used them anyway. Since that is the case with yours, you may have to do something different like I did. I'm telling you, my kids were diehard pacifier users since they were born, and I did not think it would be as easy as it was. They may surprise you!!