I'm only guessing, as I've never run into exactly this sort of template in industry, but here goes –
1. maybe templates for sign makers to cut out direction arrows on cardboard stencils?
2. maybe saw-angle-setting templates for a table saw, to set the saw fence for cutting wooden pickets of yard fences. If 4 cuts were made at same angle on the ends per template, a nice pyramid top for the pickets could be formed.
3. maybe templates for wooden wheel makers for spoke ends (or furniture makers, for chair legs)
4. maybe a template for patternmakers in a foundry for a commonly used pattern element like alignment pins or bars.
note: the holes look like they are for hanging on a nail, at least that is usually what the hole is for on templates.
note: pretty posh templates if made in stainless – most I have seen are wood, galvanized steel. or cardboard.
Who else wants a guess (or knows)?