I noticed both Pyramyd Air and Airgun Depot have notices on their sites about delays in fulfillment due to higher than normal volume of orders. And a highly reviewed Gamo .177 springer rifle I was looking at on Amazon went from 10 available to sold out in 4 days. I'm going to guess that a lot of gun guys are staying home, their shooting range is closed anyway, and ammo is scarce, so they're looking for something to shoot in the backyard or basement. There might also be a few folks thinking an air rifle might be useful for bagging small game if food supply gets disrupted. And maybe a small number of people who wanted a real firearm, but were not able to get one during the recent panic, so they figure a high powered air rifle that shoots 1000 fps is better than nothing.
The only documentation of the increase in air rifle sales was from New Zealand:
https://www.stuff.co.nz/national/health ... e-lockdown
Mair said his sales of air rifles rose from 10 in a normal week to 50 this week alone. He described those rifles as unable to kill anything due to their low velocity and believes they are sought by people wanting to fend off the tedium of lock-down. Instead, these "plinker" guns are only fit for target practice or knocking over cans, he said. "Most of it is people who think they're going to be bored."