I want to make a "boutonniere" using silk flowers, and was planning to do this by attaching the flower heads to a pin backing. When I searched for "pin blanks" online, I was expecting to find butterfly clutch types, like this:
or safety locking bar-style pins:
But, I also found some described as "coat stick pins", that look like this:
It appears that these are a traditional sort of pin which you insert through the buttonhole on the lapel (or just through the fabric, if no buttonhole). I'm not well-versed in men's formal attire, so this has me wondering: Is there any practical reason to choose this type of pin backing for a lapel pin over the other types, or is it just an aesthetic choice?