let's look at vintage check tweed

[figheadair]

The selvedge mark really makes the look work for me. I like it much more than the interwar checked kilt in Richard's other photo.

Would that be woven into the fabric with the intention of it being made into kilts?

In this particular case the plaid has decorated ends too which shows that the cloth was intended for that use rather than kilting. That said, the simple check with the herringbone selvedge mark would make a very nice kilt.