When you've dealt with Thai immigration and you understand that they are not as soft as we are in the west then you'll gladly pay a visa service. You need to experience being interviewed by an immigration officer first hand on arrival to fully understand why.
true story mate and only happened last month. I got pulled up at the Booth and taken to a desk and I think the guy was just bored to be honest killing his last hour at work. I told him I was going to do the 30 day extension he said that's just for emergency. He wouldn't listen to any reason