Long story short, the pandemic got me interested in coin roll hunting so I finally took the chance and purchased $600 in halves (full box and loose rolls). When I got home I could tell right away these had been searched a few times over (some rolls have 2 or 3 different pen marks on the side. Also, Loomis bank rolls with coins being marked on the side.)
I can imagine people get lazy, open a roll and search and put them right back in the coin wrapper. But in this case, I guess no one bothered to actually count the coins. Multiple rolls had one or two extra coins...I ended up with 17 extras. Made $8.50...not a bad first try I guess... Just hard to believe no collector or the bank for that matter bothered to count.