The slap ended up not doing anything. You also weren't lying to Jeff as when you got into the groove everything went well... and you were busy enough and no one approached the front counter so you weren't able to access the chronivac in the register. It was a little annoying you couldn't play with this seemingly reality altering machinery, but this was your job... and it didn't seem to make anyone think reality had changed so it's not like you could've just given yourself all the money in the world. This was still your job and you needed the minimum wage... and access to the chronivac. However with your shift over that was your last shift till next week... and if they called you in to work extra shifts that would probably mean not a lot of time on the register... thus not a lot of time on the chronivac.
Upset you started to leave the store, but the weird fog that had entered the cash register exited and started following you... although you didn't notice. As you entered your old car the fog followed right in your blindspot and now was in your car. Did the fog try to possess anything in the car though?