You never get asked on arrival to Thailand. The most likely is to be asked by the airline if you do not have a visa or if you have a 1 time visa, ie 60 day. If you have a visa that is multiple entry it is unlikely that you will be asked as you are able to leave at any time and return at any time......so why would you book a specific ticket.
OK I thought he was looking at a visa in country to solve his issue. Good that there is an option that does not require 400k in the bank :). Vientiane is usually the easiest for most types of visas with minimal paperwork. If he was worried he could go to a visa agent and get them to sort out the easiest option for him perhaps.