This would let shady merchants set up shop somewhere. Because it's a temporary stall, they have to come back and refresh it or empty it out, or let it lapse entirely and lose whatever is in it.
Edit for clarity:
Right now, all property signs show your true name on them when you own them. Which makes sense for permanent shops and housing. But with temporary stalls, I think it would open up a lot of RP possibilities for shady merchants if disguise names were allowed.