The statement you quoted is a business decision by the vendor - time limit 30 days or so? Who pays for all the fuses that are returned within that time period, because they didn’t like them?
With a margin of likely well over 1000%, I don't think some returns or even a lot of returns is an issue. Even 50% would be totally acceptable.
Either you make a product that people wanna keep for the duration of their expected lives, or refund them if it is faulty. Not simply because ya tried and didn't like - that is such an expensive business decision whereby the consumer takes on the risks of other consumers before him who were didn't like the fuse.
Amazon's return rate I think is close to 20%.