I dropped and shattered one of my 'free' Mason jars that came with Classico pasta sauce. It's not fixable because, despite my complaints, Classico switched to lug-style jars and doesn't sell their sauce in the nice reusable ones anymore. I'd have to actually pay for real (empty) Mason jars if I wanted to replace it. : (
Luckily, I still have plenty of extras, but still...
pedantic caveats
Yes, I know the jars aren't really 'free' if I'm paying for the sauce.
Yes, I know I ought to just make my own sauce instead of using store-bought.
Yes, I know Classico jars are technically not as thick/strong as real canning jars from Ball etc. and shouldn't actually be used for canning.
Yes, I know lug-style jars could be reused too; it's just that they aren't compatible with the universe of Mason-style canning jar attachments.