Are they a collectors item?

Depends on vintage & Brand, not as collectable any more as Fiocchi currently sells new stuff.

m4220

My 2 boxes are Winchester and it says for a mod 36 shot gun. I have a mod 36 also. One of the boxes says $4.99. I think they have been around for awhile.

Thanks,
Looks like I have others also.

Probably are collectible. Box condition is important. At the International Cartridge Show at St. Louis (April 1-4 this year)two years ago I noticed one fellow had a large collection of these miniature shot shells.
They aren't my specialty but I did notice a lot of them were in a variety of checkerboard colors.
I also saw an ad in an old American Rifleman (50's or 60's) where the ammo was for sale and an article telling of how they were used in Europe for short range pest control.
In the U.S., Winchester had a miniature skeet shooting set up using their Model 36 rifle and their 9mm shot ammo.
Check on the IAA website. There may be back Q&A's that will help you define your ammo better.