Visit AD and the daily dollar for free members.

Few days ago a new paid-to-surf program got my attention, Visit AD. The investing plan is quite simple: 7% daily for 20 days for deposits up to 500 dollars, 8% daily for deposits up to 1000 dollars and 9% daily for deposits over 1000$. Honestly my experiences with paid-to-surf or autosurf programs have never been very good so I was not interested in investing. What got my attention was an offer for free members: surf 50 sites everyday and have a free dollar. I am always interested in this kind of offers as it allows investors to test a program before putting some real money in it. That's what I am doing with Profit Clicking too, playing with the initial 10$ bonus.
The day I joined I surfed 50 sites and the next day 1$ was accredited in my account. Good. The second day  I wanted to surf 50 sites too but... the Start to Rate button (which opened the surfing interface) was not there anymore. Why? Because the rules changed.
Now, I understand that giving a free dollar everyday to all the free members can definitely destroy a program, but the admins should know it when he launched the site. What's the point of offering something and removing the offer in just few days? Is it a marketing technique?
I really can't understand.