When we used to feed the bird population of East London (prior to the arrival of a cat) I used to make my own suet sticks, very easy, more economical and easier to deploy.
Suet/lard from sainsbury/tesco with oats/grain/bulk peanuts/sunflower seeds/cheap dried fruit/whatever. Heat the fat to melt and stir in the gubbins. I used old sealant tubes or bits of drain pipe to set them in, then placed in a feeder. Any issues pushing it out, just warm lightly. Of course it is a bit more faffage than buying, but fun all the same.