At my store, we routinely do this for OPU carts. When a TM starts an OPU batch they name the cart SHPFirstnameInitial,LastnameInitial so for example, Joe Smith would be SHPJS. Helps us keep track of who is doing what. For SFS we have a yellow legal pad hanging up on the wall and every Fulfillment TM is required to write down their name, the cart they are using and the time they started their batch. So Bob Smith would log, Bob Smith, SHPQA, 10:15am. This helps the captains and TLs keep track of who is doing what and it lets the packing TMs know who picked the cart they are packing in the event any items are missing. "Hey Ann Smith, the Star Wars Lego you scanned into SHPQB isn't here - what do you know about that?"
That being said, it doesn't sound like to much of a programming enhancement to be able to add initials to any cart, SFS or OPU.