Loved finding out about glue basting with washable glue sticks. I used it a lot when I was making the blocks for the plaid shirt string quilt.
I now use that knowledge at times when I'm sewing garments. Sometimes it takes a jillion pins (like setting sleeves) and its hard to sew without hitting one and breaking a needle. My handy little glue stick buddies avoid all of that.
As for the actual question, I use it any time I want to avoid sliding. I haven't been brave enough to make blocks where it's crucial for the points to line up yet, (bawk, baaawwwk!) but when I do, I'll def be using glue sticks. I still haven't gotten a little metal lid, but I'm going to try that 2 oz bottle idea first. Then the large bore blunt needle syringes, *then* I'll break down and buy one. They're ridiculously expensive IMHO.