Expensive in terms of effort, yes. There must be several opportunities for higher brain function to over-ride the reptile brain before a bet is placed.
New federal law: all gambling bets must be placed by fax or mail accompanied by a legible signature, with results to be released no less than 24 hours after betting closes.
You jest but a serious proposal on the table in Brasil right now is constant/ongoing facial recognition on online betting sites to authorise the session.
Indeed. Expensive in terms of money it already is, and it's not effective.
Sports betting sites generally have margins well under 10%. That's not expensive IMO.