The round up thing has been going on for a while, even before the pandemic. At least one on-line vendor has been doing the round up for the NRA for years. My local pet store has round up for the Humane Society and now CVS has round up for some medical charity. It is not just to avoid change as they still give you the option when using a credit card. I have mostly been using credit cards for all my purchases for years and years to get the cash back bonus of course you probably know that Gun Shop and Gun Show vendors charge extra to use a credit card. I carry cash and carry extra to gun shows but mostly use the cards.
Tim