The only thing I use them for is to sew down the accent strip on burrito style pillowcases. I make special ones for holidays, birthdays, special interests, for our grandchildren. i don't always put one in, opting instead to just have the main fabric and cuff, but when I do put one on, I like to stitch the outside edge down so it stays flat.
I have used the alphabet stitch to put a special message on a project - either pillowcases above or in a border or on binding.
My Bernina is over 20 years old, and I'd replace it with another in a heartbeat if they had one that didn't include all of the high end bells and whistles. The shop where I bought it no longer carries any Berninas except the 300 level; they carry Juki's now, for just that reason. They've had many people say that they don't want all of that "stuff", they want a beautiful straight stitch.