maybe their techniques have changed since they first started but I remember cafepress having cheap iron-on graphics that were destroyed through one wash cycle. zazzle looks like more of the same. if you're a business it's not the best route to go imho, especially if you're starting out. also, these sites mass produce the same things and tend to stick to the "quantity not quality" mantra of doing business. their business model doesn't inspire confidence imo. I would rather order a quality screen-printed t-shirt from a struggling company that only has 12 designs than some poor looking cafepress/zazzle company that has thousands of poor designs.
Yes, most businesses improve over time
CafePress using high end DTG printers for their printing. Zazzle does the same.
As I said, there are lots of businesses (both big and small) that use places like CafePress and
Zazzle for their printing. Talking about bigger names like Disney, Star Wars, KISS, The Library of Congress, Star Trek, March of Dimes, etc.
I don't think you can really tell the quality of printing Zazzle produces by looking at their website.
Just like all businesses, the products go through several quality control checks before leaving. Just like most businesses, humans can sometimes make an error. Even at 1% error (just making up a number), you're going to have more errors when you're doing 1000's of t-shirts per day than if you're doing hundreds.
As another member pointed out, there are people making good income, repeat customers, who have savvy business smarts using CafePress, Zazzle and other print on demand sites.
You seem to be making a lot of assumptions that aren't based on actual facts (or maybe just outdated facts).
I can definitely understand preferring screen printed t-shirts to tees that are printed on demand. There's something to be said for the beauty of a quality screen printed t-shirt, but buying a screen printed t-shirt isn't an automatic guarantee of quality just as buying a t-shirt from a print on demand powered store doesn't automatically mean a lack of quality.
I guess my point is that that painting everything with big broad brush stroke generalizations isn't taking a realistic view on what's really possible with these sites.