DL SEA Counter Shut Down as Passenger Abandoned Baggage Due to Fees

Would you pay the $1,400 charge for overweight luggage, or just leave your bag and buy some new clothes? A Delta passenger understandably took the latter option - but if you are familiar with the constant "do not leave unattended luggage" announcements at airports, you can imagine the trouble it caused.
Heading to JFK from SEA on Tuesday, a frustrated traveller left his baggage at the Delta check-in desk rather than face the extortionate fees for having overweight luggage, according to NBC News.

Innocent it may seem, but sure enough the Delta lobby was promptly shut down for over two hours, as security jumped on the unattended belongings, subjecting them to x-rays, inspections and even analysis from bomb technicians.
After this time, the abandoned luggage was determined not to be threatening and Seattle's airport security tracked down the owner and his flight. According to Yahoo Finance, finding unattended baggage is not an unusual occurrence for Delta.

How in the world do you get baggage fees that high? Unless you have a half dozen bags filled to the brim, which doesn't seem to be the case. Maybe the bag weighed in at over 100 pounds, then had to be considered cargo instead of a checked bag?