Lightning, when you say curly, do you mean like cotton Lycra? I’ve sewn a lot with that, and leaving the seams unfinished has not been a problem. They look good and wash well.
I agree that home made should be high quality. For wovens, centuries of experimentation went into developing hand and machine methods work working fabrics to demonstrate quality and ensure the longevity of the garment.
This cannot be said of knit fabrics. With knits, we’re working textiles that could only be created by industrial machinery. The historical repertoire of techniques comes from that machinery, and from efforts to create what consumers would recognize as markers of quality – like overlocked seams. But industrially-produced knit garments are, in general, not produced to high quality standards.
Finishing seams does add strength. It can also make them really scratchy, and overworking a seam can result in the fabric getting stretched out and lettuce-y. If you have a serger, by all means, serge away! If not, a raw seam works just fine. Your finished product won’t look industrial from the inside. That’s OK.
TL;DR: I’ve been making knit garments for years. I leave seams unfinished. It has never been a problem.
