I think free overnight is still possible when purchasing online. Verizon saves a LOT of money when people purchase online vs. over the phone, so it wouldn't make sense for them to offer an incentive to choose telesales vs the website. See this note that I found on Verizon's website (particularly, the promo code):
Free Overnight Shipping
Enjoy free overnight shipping* when you order online Monday - Friday by 4:30 pm! Some customers may need to select Overnight shipping option in drop down and enter promo code FREEOVERNT at checkout.
Signature will be required upon delivery.
*Free Overnight Shipping is available for purchases placed on VerizonWireless.com within the U.S. only, excluding Alaska and Hawaii. Orders placed by 4:30 pm local time Monday ? Friday excluding holidays will deliver by the next business day. (Orders placed after 4:30 pm local time on Friday and before 4:30 pm local time on Monday will deliver on Tuesday.) Subject to credit authorization, verification and inventory availability.