There have probably been more bomb threats these last few weeks than there have been in the last 6 months. Law enforcement, HAZMAT, firemen and other assorted responders, including sniffing dogs must be thinking...."Oh no....not another one". And at this point, the stink bomb emerges.....harmless, but nauseating. One was released in a library:

"Canyon City police and firefighters were called out to the public city Library on Thursday around 2:15 p.m. because someone reported smelling noxious fumes.
Library staff evacuated the building after smelling a strong sulfur-like odor and noticing glass shards on the floor. Two Library patrons were transported to the hospital after complaining of shortness of breath.
They were later released.
Firefighters ventilated the building.
They also recovered glass shards that are believed to have contained the noxious substance.
These were turned over to police for processing.
Some of the glass shards were reassembled and appear to resemble glass vials used in “stink bombs”.
It is believed that they contained ammonium sulfide but this has not been confirmed.
At this time there are no suspects."

There was also a stink bomb released in a hospital emergency room over the weekend.
The events over the last few weeks are turning America into a collage of hoaxes, pranks and copy-cat threats! BUT among them, the REAL THREAT is lurking and accomplishing it's goal which is citizen fatigue leading into the real attack.
People are also becoming dangerously desensitized to the threats and in some cases, the evacuation isn't carried out immediately because store, restaurant owners, etc are delaying calling authorities in some cases where there have already been multiple HOAX threats. In one instance, a man walked into a store and said there would be a bomb going off later that night. No one was evacuated because the store wasn't open at night.
It's obvious that a party or parties may be actually aiming these hoax threats at citizens to accomplish an atmosphere of delayed, desensitized response. And just when the time is ripe, a REAL BOMB will be released in 50 stores across the nation simultaneously.
Now, who do you think stands to benefit from bomb threat desensitization and fatigue? Who benefits from watching security responses nationwide? Who benefits from hoax-weary citizens who've been stink-bombed into a nonchalant oblivion?
I can guarantee you it's not dumb kids seeking to get out of classes for the day.