> Do you patch your socks, shirts, pants, jackets?

Socks, generally no - by the time they've got holes, they're usually overall worn down anyway.

I don't generally patch t-shirts or boxers (same reason), but I do sew worn seams, and patch pants, sweaters and jackets. I don't personally replaces zippers, but there's a local shop that does.

For eg gortex outwear, it's possible to fix minor holes (like from sparks from a bonfire) with repair tape.