In regards to J. Crew bags: I picked up a messenger bag on sales about 2-3 years ago for $30 or so. I used it every day, carrying a lot of crap. I used to throw it around everywhere too. It's held up fine, no holes or tears.
As a former J. Crew employee...the quality has nose dived in certain things the last couple years...including messenger bags. Perhaps you bought one when the quality was still decent. Some stuff has stayed pretty consistent like the secret washed shirts, but overall the stuff isn't like how it was even 3-4 years ago.