There is most definitely a need to restrict entry into the terminal building, for crowd control more than security! The method employed isn't necessarily ideal though.

What they need is for all airlines to use a barcode on their e-tickets, boarding passes, printouts and email confirmations. That, with a simple scanner next to the pandu at the entrance, will solve half the problems and ameliorate the other half.

It can do much more, if used right, but let's aspire for the basics first.