Luke 10 - Daunting Duties

I guess the best thing you can do when sending people into a dangerous situation is to warn them. At least that gives them some idea of what they are getting themselves into. "Go! I am sending you out like lambs among wolves." would probably qualify as a fair warning. How is that for a challenge.

Jesus follows this up with curious instructions. "Do not take a purse or bag or sandals." I get that this meant they were to rely completely on God. What I don't get is the next instruction, "and do not greet anyone on the road." Why not? This couldn't have been for their protection, they were already completely reliant on God for that. What was it about others on the road?